Near-Field Cosmology with the Lowest-Mass Galaxies, by Daniel Weisz, University of California, Berkeley NASA ADS record: 2019BAAS...51c...1W/abstract We present an overview of near-field cosmology and make recommenations for future progress. The study of nearby low-mass galaxies on a star-by-star basis has implications that extend far beyond the local Universe and include the nature of dark matter, lives and deaths of the first stars, cosmic reionization, and galaxy formation across cosmic time.
ELT Contributions to The First Explosions, by J. Craig Wheeler, The University of Texas at Austin NASA ADS record: 2019BAAS...51c...3W/abstract We describe the potential for using Type Ia supernovae, pair instability supernovae, superluminous supernovae, and gamma-ray bursts to probe the first explosions and hence first stars in the Universe with a US-ELT System.
ELT Contributions to Tidal Disruption Events, by J. Craig Wheeler, The University of Texas at Austin NASA ADS record: 2019BAAS...51c...4W/abstract A US-ELT system with its large aperture and sensitive optical and near infrared imager spectrographs will make major contributions to the study of stars ripped apart by supermassive black holes.
Method to aluminum-coat telescope mirrors in space for EUV-broadband astronomy, by David Sheikh, ZeCoat Corporation NASA ADS record: 2019astro2020T...7S/abstract Telescope mirrors and gratings coated on-orbit with bare aluminum may allow broadband observations that include the EUV band between 30-nm and 100-nm and would have broadband coverage from the EUV through the long IR. High-discharge lithium battery technology exists today to build a large, self-coating telescope in space.
Solar flares and Quantum Neural Networks, by Ashwini Sathnur, United Nations Development Programme NASA ADS record: 2019BAAS...51c...9S/abstract Introduction of new technologies on the conceptual ideologies of Accessibility. This white paper describes the innovative themes of solar flares and the realization of implementation of new technologies. The human astronauts end users are located in the space regions where there could be incidents of exposure to the solar flares and the radiation.
An Arena for Multi-Messenger Astrophysics: Inspiral and Tidal Disruption of White Dwarfs by Massive Black Holes, by Michael Eracleous, The Pennsylvania State University NASA ADS record: 2019BAAS...51c..10E/abstract Tidal disruptions of white dwarfs by intermediate-mass black holes can inform us of black hole demographics, stellar populations and dynamics in their vicinity, and the physics of accretion. We can harness the information with a combination of surveys surveys for electromagnetic observatories and low-frequency gravitational wave observations.
JWST/MIRI Surveys in GOODS-S, by George Rieke, University of Arizona NASA ADS record: 2019BAAS...51c..11R/abstract JWST/MIRI GTO programs in GOODS-S will (1) measure obscured star formation rates down to 10 Mʘ/yr; (2) measure aromatic band strengths to constrain processes in galaxy ISMs; (3) complete our inventory of AGN types; (4) improve mass estimates for galaxies at z > 4; and (5) help determine masses and ages of young stellar populations at z > 8.
Exoplanet Diversity in the Era of Space-based Direct Imaging Missions, by Ravi kumar Kopparapu, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c..12K/abstract This whitepaper discusses the diversity of exoplanets that could be detected by future observations in the upcoming era of large space-based flagship missions. The primary focus will be on characterizing Earth-like worlds around Sun-like stars. However, we will also be able to characterize companion planets in the system simultaneously.
Understanding Accretion Outbursts in Massive Protostars through Maser Imaging, by Todd Hunter, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c..13H/abstract Two recent extraordinary accretion outbursts in massive protostars, both heralded by maser flares, have impacted our view of star formation. Unraveling the accretion mechanism in such deeply-embedded systems requires larger, more sensitive centimeter wavelength interferometers to image the masing molecular gas simultaneously with the ionized gas.
The Role of Machine Learning in the Next Decade of Cosmology, by Michelle Ntampaka, Harvard Data Science Initiative; Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c..14N/abstract Machine learning (ML) methods have remarkably improved how cosmologists can interpret data. The next decade will bring new opportunities for data-driven discovery, but will also present new challenges for adopting ML methodologies. ML could transform our field, but it will require the community to promote interdisciplinary research endeavors.
Comparing key compositional indicators in Jupiter with those in extra-solar giant planets., by Jonathan Lunine, Cornell University NASA ADS record: 2019BAAS...51c..15L/abstract James Webb Space Telescope will enable detailed analysis of molecular abundances, including but not limited to all the major carbon- and oxygen-bearing species in hot Jupiter atmospheres. This will allow determination of the carbon-to-oxygen ratio, an essential number for planet formation models and allowing comparison with Juno's value for Jupiter.
From Dark Energy to Exolife: Improving the Digital Information Infrastructure for Astrophysics, by Michael Kurtz, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c..17K/abstract A robust information infrastructure is needed to meet future research challenges. The scientific literature can be used as the central organizing point used to navigate interdisciplinary research fields. Connecting the literature with data products increases discoverability of both and allows for the data to be more accessible by non-experts.
Solar System Science with Space Telescopes, by Roser Juanola-Parramon, NASA GSFC/UMBC NASA ADS record: 2019BAAS...51c..18J/abstract Building on the legacy of HST and other space telescopes, a large multi-wavelength space observatory would enable transformative advances in planetary science. Here we highlight several representative areas of Solar System science that would greatly benefit from high resolution UV/Opt/NIR imaging (Venus, Jupiter, Neptune, dwarf planets and KBOs).
Potential for Solar System Science with the ngVLA: the Giant Planets, by Imke de Pater, UC Berkeley NASA ADS record: 2019BAAS...51c..19D/abstract Radio wavelength observations of solar system bodies are a powerful method of probing the deep atmospheres of the giant planets, its rings, and magnetospheres. The ngVLA will enable the highest sensitivity and resolution observations of this kind, with the potential to revolutionize our understanding of these bodies.
The Magellanic Stream as a Probe of Astrophysics, by Andrew Fox, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c..20F/abstract The Magellanic Stream is the most spectacular example of a gaseous stream in the local Universe. In this white paper, we emphasize the Stream's importance for many areas of Galactic astronomy, summarize key unanswered questions, and identify future observations and simulations needed to resolve them.
Spectroscopic Observations of the Fermi Bubbles, by Andrew Fox, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c..21F/abstract The Fermi Bubbles are two giant plasma lobes extending 10 kpc above and below the Galactic Center. Here we identify the scientific themes that have emerged from spectroscopic studies of the Bubbles, determine key open questions, and describe the observations needed in the next decade to characterize the nuclear wind and its impact on the Galaxy.
Solar System Science with the James Webb Space Telescope, by Heidi Hammel, AURA NASA ADS record: 2019BAAS...51c..22H/abstract NASA's space telescopes advance Solar System exploration in ways that complement in situ planetary spacecraft. As an example, we review some of the Solar System science planned for the James Webb Space Telescope. We envision similar robust planetary science cases for other future astrophysics flagships, particularly LUVOIR.
X-rays Studies of the Solar System, by Bradford Snios, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c..25S/abstract X-ray observatories advance Solar System studies by probing Sun-object interactions, developing surface composition maps, probing magnetospheric dynamics, and tracking astrochemical reactions. Implementing modern X-ray optics in future instruments will foster a truly transformative era of Solar System science through the study of X-ray emission.
X-ray Studies of Exoplanets, by Scott Wolk, Smithsonian Astrophysical Observatory NASA ADS record: 2019BAAS...51c..28W/abstract We discuss contributions to the study of exoplanets and their environs which can be made by X-ray data of increasingly high quality that are achievable in the next 10--15 years.
Intermediate-Mass Black Holes in Extragalactic Globular Clusters, by Joan Wrobel, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c..29W/abstract Intermediate-mass black holes have masses of ~ 100 to 100,000 Msun. Finding them in globular clusters would validate a formation channel for seed black holes in the early universe and inform event predictions for gravitational wave facilities. Searching many globular clusters is key, and only feasible using a next-generation Very Large Array.
Habitable zone predictions and how to test them, by Ramses Ramirez, Earth-Life Science Institute (ELSI), Tokyo Institute of Technology NASA ADS record: 2019BAAS...51c..31R/abstract The classical HZ definition makes a number of assumptions common to the Earth. We discuss these and the observations needed to test them. We also discuss how next-generation missions are only the beginning of a much more data-filled era in the near future, allowing us to actually determine which planets are most likely to exhibit life.
Tests of General Relativity and Fundamental Physics with Space-based Gravitational Wave Detectors, by Emanuele Berti, Johns Hopkins University NASA ADS record: 2019BAAS...51c..32B/abstract Low-frequency gravitational-wave astronomy can perform precision tests of general relativity and probe fundamental physics in a regime previously inaccessible. A space-based detector will be a formidable tool to explore gravity and some of the greatest mysteries in physics and astronomy, such as dark matter and the origin of the Universe.
Ultraviolet Spectropolarimetry as a Tool for Understanding the Diversity of Exoplanetary Atmospheres, by Luca Fossati, Space Research Institute, Austrian Academy of Sciences NASA ADS record: 2019BAAS...51c..33F/abstract We show that a high-resolution spectropolarimeter with a broad wavelength coverage, particularly if attached to a large space telescope, would enable simultaneous study of the polarimetric exoplanet properties of the continuum and to look for and characterize the polarimetric signal due to scattering from single molecules.
Populations behind the source-subtracted cosmic infrared background anisotropies, by Alexander Kashlinsky, Goddard Space Flight Center NASA ADS record: 2019BAAS...51c..37K/abstract Source-subtracted CIB fluctuations cannot be explained by known galaxy populations and appear highly coherent with unresolved CXB from significantly abundant accreting BHs. Characterizing the CIB with high accuracy, and constraining the nature of the new populations would produce critically important cosmological information in the next decade.
A Summary of Multimessenger Science with Neutron Star Mergers, by Eric Burns, NASA Goddard NASA ADS record: 2019BAAS...51c..38B/abstract The white paper discusses the breadth of science that is possible with multimessenger observations of neutron star mergers. It then makes recommendations for the next decade, then beyond, to be sure we capture this science.
Spectroscopic Probes of Galaxies at the Epoch of Reionization, by Marusa Bradac, UC Davis NASA ADS record: 2019BAAS...51c..39B/abstract While JWST will revolutionize the study of galaxies at the epoch of reionization, several questions will remain unanswered even after the data is taken. ELTs will provide a comprehensive picture on the properties of Lyman-alpha emitters, and establish them as one of the main probes of the reionization epoch.
Cosmic voids: a novel probe to shed light on our Universe, by Alice Pisani, Princeton University NASA ADS record: 2019BAAS...51c..40P/abstract In this paper we present the case for void science, arguing that cosmic voids are a novel probe to constrain modified gravity, dark energy, the sum of neutrino masses and galaxy evolution. Voids will answer some of the most relevant questions in cosmology and astrophysics over the next decade.
Imaging molecular gas in high redshift galaxies at <=1 kpc resolution, by Christopher Carilli, NRAO NASA ADS record: 2019BAAS...51c..41C/abstract Imaging the cool molecular gas in distant galaxies, the fuel for star formation, at <= 1kpc resolution, is a prerequisite for future 'precision galaxy formation studies', addressing such basic issues as a Universal 'star formation law', cloud evolution and feed-back, and the dynamics and physical conditions in the cold gas in early galaxies.
The unique potential of extreme mass-ratio inspirals for gravitational-wave astronomy, by Christopher Berry, Northwestern University NASA ADS record: 2019BAAS...51c..42B/abstract EMRIs are a prime source for LISA. They will tell us about the stellar dynamics in galactic nuclei and massive black hole populations. They will enable percent-level measurements of the multipolar structure of massive black holes and tests of the strong-gravity regime. They may also provide cosmographical data about the expansion of the Universe.
Science from an Ultra-Deep, High-Resolution Millimeter-Wave Survey, by Neelima Sehgal, Stony Brook University NASA ADS record: 2019BAAS...51c..43S/abstract Opening up a new window of millimeter-wave observations that span frequency bands in the range of 30 to 500 GHz, survey half the sky, and are both an order of magnitude deeper and of higher-resolution than currently funded surveys would yield an enormous gain in understanding of both fundamental physics and astrophysics.
JWST GTO/ERS Deep Surveys, by Marcia Rieke, University of Arizona NASA ADS record: 2019BAAS...51c..45R/abstract Discovering and characterizing the first galaxies to form in the early Universe is one of the prime reasons for building a large, cold telescope in space, JWST. This white paper describes an integrated GTO program using 800 hours of prime time and 800 hours of parallel time to study the formation and evolution of galaxies from z ~2 to z~14.
The Extended Cool Gas Reservoirs Within z > 1 (Proto-)Cluster Environments, by Kevin Harrington, Argelander Institute for Astronomy, Bonn, Germany NASA ADS record: 2019BAAS...51c..46H/abstract This work focuses on the major role large radio/millimeter (mm) single dish facilities will have in constraining the bulk, cold molecular and atomic gas content. We calculate how the high-sensitivity of the GBT's unblocked 100m aperture provides vital interferometric short-spacing coverage to support higher-resolution ngVLA observations.
Cosmic Dawn and Reionization: Astrophysics in the Final Frontier, by Asantha Cooray, UC Irvine NASA ADS record: 2019BAAS...51c..48C/abstract The cosmic dawn and epoch of reionization mark the time period in the universe when stars, galaxies, and blackhole seeds first formed and the intergalactic medium changed from neutral to an ionized one. This white paper outlines the current state of knowledge, anticipated scientific outcomes in the 2020s and scientific goals for new facilities
The Potential of Ultraviolet Spectroscopy to Open New Frontiers to Study the First Stars, by Ian Roederer, University of Michigan NASA ADS record: 2019BAAS...51c..49R/abstract The elements found in second-generation stars probe the nature and end states of the elusive generation of metal-free first stars. High-resolution (R ≥ 30,000) ultraviolet (~1800-3100 Å) spectroscopy offers the potential to greatly expand the chemical inventory in second-generation stars. Facilities like CETUS, HabEx, and LUVOIR meet these goals.
Early evolution of galaxies and of large-scale structure from CMB experiments, by Gianfranco De Zotti, INAF-Osservatorio Astronomico di Padova NASA ADS record: 2019BAAS...51c..50D/abstract Next generation CMB experiments with arcmin resolution will, for free, lay the foundations for a real breakthrough on the study of the early evolution of galaxies and galaxy clusters, thanks to the detection of large samples of strongly gravitationally lensed galaxies and of proto-clusters of dusty galaxies up to high redshifts.
Electromagnetic probes of primordial black holes as dark matter, by Alexander Kashlinsky, Goddard Space Flight Center NASA ADS record: 2019BAAS...51c..51K/abstract Next decade, new space- and ground-borne electromagnetic instruments, combined with concurrent theoretical efforts, should shed critical light on the link between primordial Black Holes and Dark Matter. We summarize the prospects to resolve this important issue with electromagnetic observations using instruments and tools expected in the 2020's.
UV Exploration of the solar system, by Jean-Yves Chaufray, LATMOS/IPSL, CNRS NASA ADS record: 2019astro2020T..52C/abstract The UV spectral range is a crucial window to investigate a large area of phenomena for the objects of the solar system from the surface to the atmosphere and magnetosphere. In this white paper, we describe how future UV observations with high spectral resolution and polarimetric capability will bring new information on those subjects.
Direct Acceleration: Cosmic and Exoplanet Synergies, by David Erskine, Lawrence Livermore National Laboratory NASA ADS record: 2019BAAS...51c..53E/abstract 4 frontier science areas can make great strides with development of highly accurate and stable spectroscopy: • Cosmic redshift drift and direct detection of cosmic acceleration • Earth mass exoplanet detection from radial velocities • Milky Way structure mapping through stellar accelerations • Dark matter properties thru Milky Way gravity mapping
Radio sources in next-generation CMB surveys, by Gianfranco De Zotti, INAF-Osservatorio Astronomico di Padova NASA ADS record: 2019BAAS...51c..54D/abstract Next-generation CMB experiments will provide samples of thousands radio sources allowing the investigation of the evolutionary properties of blazar populations, the study of the earliest and latest stages of radio activity, the discovery of rare phenomena and of new transient sources and events.
Stars at High Spatial Resolution, by Kenneth Carpenter, NASA's Goddard Space Flight Center NASA ADS record: 2019BAAS...51c..56C/abstract We summarize compelling new scientific opportunities for understanding stars and stellar systems that can be enabled by sub-milliarcsec angular resolution, UV/Optical spectral imaging observations. These can reveal details of many dynamic processes that affect stellar formation, structure, and evolution.
A proposal to exploit galaxy-21cm synergies to shed light on the Epoch of Reionization, by Anne Hutter, Kapteyn Astronomical Institute, University of Groningen NASA ADS record: 2019BAAS...51c..57H/abstract This white paper outlines the benefits of synergizing WFIRST, Subaru Hyper Suprime-Cam or other >25m-class telescopes galaxy observations with SKA 21cm measurements to constrain the nature of reionization (ionization history and topology) and its sources.
Direct Imaging and Spectroscopy of Exoplanets with the James Webb Space Telescope, by Charles Beichman, NASA Exoplanet Science Institute, IPAC, JPL/Caltech NASA ADS record: 2019BAAS...51c..58B/abstract Coronagraphic imaging and direct spectroscopy of young planets with JWST will add new insights into our understanding of the formation and evolution of exoplanets. This paper focuses on how JWST will add to our knowledge of young giant planets located at orbits beyond a few AU for the closest stars and a few 10s of AU for more distant ones.
Opportunities for Astrophysical Science from the Inner and Outer Solar System, by Michael Zemcov, Rochester Institute of Technology NASA ADS record: 2019BAAS...51c..60Z/abstract Astrophysical measurements away from the 1 AU orbit of Earth can enable several astrophysical science cases that are challenging or impossible to perform from Earthbound platforms. In this White Paper, we describe the science motivations and advocate for flight opportunities to make these science investigations a reality.
Characterizing Transiting Exoplanets with JWST Guaranteed Time and ERS Observations, by Thomas Greene, NASA Ames Research Center NASA ADS record: 2019BAAS...51c..61G/abstract We highlight how guaranteed time observations and early release science will advance understanding of exoplanet atmospheres and provide a glimpse into what transiting exoplanet science will be done with JWST during its first year of operations. JWST will be the most important mission for characterizing exoplanet atmospheres in the 2020s.
Supermassive Black Hole Spin and Reverberation, by Abderahmen Zoghbi, University of Michigan NASA ADS record: 2019BAAS...51c..62Z/abstract X-ray reverberation mapping has emerged as a powerful probe of microparsec scales aroundAGN, and with high sensitivity detectors, its full potential in echo-mapping the otherwise inaccessible disk-corona at the black hole horizon scale will be revealed.
Cosmology with the Highly Redshifted 21 cm Line, by Adrian Liu, McGill University NASA ADS record: 2019BAAS...51c..63L/abstract The 21cm line can be used to conduct large-volume surveys of the high-z universe, probing both astrophysics and cosmology. We highlight the promise of using the 21cm line to constrain cosmology via z>6 observations, emphasizing the key advances and investments required to access the potentially vast information content of future surveys.
Investigating the Solar System's Ocean Worlds with Next-Generation Space Telescopes, by Marc Neveu, University of Maryland, College Park / NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c..65N/abstract The search for life on the solar system's ocean worlds must involve space telescopes uniquely able to observe numerous distant targets at high spatial resolution, for nearly arbitrary amounts of time, unimpeded by the Earth's atmosphere. Questions drawn from the NASA Roadmap to Ocean Worlds best addressed by telescopic measurements are presented.
The Life Cycle of Dust, by Sarah Sadavoy, Harvard-Smithsonian Center for Astrophysics NASA ADS record: 2019BAAS...51c..66S/abstract White paper describes efforts to improve our understanding of the life cycle of dust. Paper highlights the need for multi-wavelength spectroscopy and continuum observations to study the main sources of dust production and how grain compositions and grain sizes change locally and across cosmic time.
"It's full of asteroids!â€: Solar system science with a large field of view, by Bryan Holler, STScI NASA ADS record: 2019BAAS...51c..68H/abstract Next-generation space telescopes will have larger apertures, larger fields of view, and more sensitive instrumentation than their predecessors. The prospects for solar system science with these facilities are substantial, particularly in the area of space-based surveys for the detection of new minor bodies and irregular satellites.
Modeling Debris Disk Evolution, by Andras Gaspar, Steward Observatory, The University of Arizona NASA ADS record: 2019BAAS...51c..69G/abstract Understanding the formation, evolution, and architectures of planetary systems requires detailed knowledge of their components. Debris disks provide a means with which we can study them. The next decade will deliver a wealth of new information on the nearest systems. Parallel advances in modeling will be necessary to interpret these new datasets.
Cooking with X-rays: Can X-ray binaries heat the early Universe?, by Antara Basu-Zych, UMBC/CRESST, NASA/GSFC NASA ADS record: 2019BAAS...51c..70B/abstract X-rays from high mass X-ray binaries within the first primordial galaxies likely played a significant role in heating the early Universe at z>10. Combining observations from next generation X-ray telescopes with upcoming measurements of the cosmic 21-cm signal will have the power to offer important insights into conditions in the early Universe.
Cold Gas Outflows, Feedback, and the Shaping of Galaxies, by Alberto Bolatto, University of Maryland at College Park NASA ADS record: 2019BAAS...51c..71B/abstract This paper outlines several key open questions on galaxy outflows, particularly cold outflows, and the associated feedback. After laying out the questions we briefly discuss the requirements of the observations necessary to make progress, and the relevance of several existing and planned facilities.
Inflation and Dark Energy from spectroscopy at z > 2, by Simone Ferraro, Lawrence Berkeley National Laboratory NASA ADS record: 2019BAAS...51c..72F/abstract Multi-Object Spectroscopy at 2 < z < 5 can greatly improve our understanding of Inflation, Dark Energy and neutrino masses, while relaxing some restrictive modeling assumptions.
Disentangling nature from nurture: tracing the origin of seed black holes, by Priyamvada Natarajan, Yale University NASA ADS record: 2019BAAS...51c..73N/abstract The origin of seed black holes is fiercely debated and is one of the key open questions in cosmology today. Gravitational wave events from supermassive binary black hole coalescences coupled with multi-messenger data can help disentangle initial seeding conditions from accretion and dynamics that modulate black hole growth over cosmic time.
Finding Exo-Earths with Precision Space Astrometry, by Michael Shao, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c..74S/abstract Astrometry may be the only technique capable of finding Earth-twins. It measures the reflex motion of a star in the plane of the sky allowing one to determine a planet's mass and its orbital inclination. Astrometric measurements with 1 uas precision allow to search for a 1 M_earth planet in the middle of the habitable zone.
The physics and astrophysics of X-ray outflows from Active Galactic Nuclei., by Sibasish Laha, University of California, San Diego NASA ADS record: 2019BAAS...51c..75L/abstract AGN outflows are integral for understanding how the central super massive black hole interacts with the host galaxy and co-evolves in cosmic time. This white paper sets the primary science goals for the next decade and suggests the key parameters on which the next generation X-ray telescopes should be built to revolutionize our understanding.
The Discovery Potential of Space-Based Gravitational Wave Astronomy, by Neil Cornish, Montana State University NASA ADS record: 2019BAAS...51c..76C/abstract A space-based interferometer operating in the previously unexplored mHz gravitational band has tremendous discovery potential. If history is any guide, the opening of a new spectral band will lead to the discovery of entirely new sources and phenomena.
Solar System Science with a Space-based UV Telescope, by John Clarke, Boston University NASA ADS record: 2019BAAS...51c..77C/abstract Broad and scientifically critical observations of solar system bodies can be performed with either of the Astrophysics UV/visible telescopes currently under study (HabEx or LUVOIR). This white paper describes briefly a subset of the planetary science objectives that can only be met from above the atmosphere.
Looking Under a Better Lamppost: MeV-scale Dark Matter Candidates, by Regina Caputo, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c..78C/abstract Two well-motivated dark matter candidates are weakly interacting massive particles (WIMPs) and weakly interacting sub-eV particles (WISPs) (e.g. axions). A new gamma-ray telescope that is optimized for MeV energies would allow us to explore new areas of dark matter parameter space and provide unprecedented access to its particle nature.
Searching for Technosignatures: Implications of Detection and Non-Detection, by Jacob Haqq-Misra, Blue Marble Space Institute of Science NASA ADS record: 2019BAAS...51c..79H/abstract The search for technosignatures from the Galaxy or the nearby universe raises two main questions: What are the possible characteristics of technosignatures? and How can future searches be optimized to enhance the probability of detection? Addressing these questions requires an interdisciplinary approach, which is described in this white paper.
Realizing the Unique Potential of ALMA to Probe the Gas Reservoir of Planet Formation, by Ilse Cleeves, University of Virginia NASA ADS record: 2019BAAS...51c..81C/abstract ALMA has revolutionized our view of protoplanetary disks, revealing structures in dust emission likely sculpted by forming planets. Studying how gas assembles into planets and its broader chemical makeup requires higher spectral line sensitivity than currently possible. Accomplishing this science requires a major upgrade of ALMA in the 2030s era.
The hidden circumgalactic medium, by Claudia Cicone, INAF - Osservatorio Astronomico di Brera NASA ADS record: 2019BAAS...51c..82C/abstract The properties of the CGM are directly linked to the baryon cycle. Although traditionally the CGM should consist of warm/hot gas, recent breakthroughs suggest that a significant mass resides in a cold phase, which is filtered out by interferometers. The only way to probe such cold CGM is through a large (e.g. 50-m) single dish (sub-)mm telescope.
The Local Relics of of Supermassive Black Hole Seeds, by Jenny Greene, Princeton University NASA ADS record: 2019BAAS...51c..83G/abstract In the coming decade we will have the capability to dynamically detect 1000 to hundred thousand solar mass black holes should they exit. This white paper describes how measuring the mass function of the elusive intermediate-mass black holes will provide unique insight into the formation of the first massive black holes.
Increasing the Discovery Space in Astrophysics: The Exploration Question for Resolved Stellar Populations, by Giuseppina Fabbiano, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c..84F/abstract Exploration can be the central question for Astro2020. Major astronomical discoveries were not driven by known questions, but by increasing discovery space via new telescopes and instruments, & now archive mining. Revolutionary facilities and supporting archives will open new discoveries. Here we focus on exploration of resolved stellar populations
Increasing the Discovery Space in Astrophysics The Exploration Question for Stars and Stellar Evolution, by Giuseppina Fabbiano, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c..85F/abstract Exploration can be the central question for Astro2020. Major astronomical discoveries were not driven by known questions, but by increasing discovery space via new telescopes and instruments, & now archive mining. Revolutionary facilities and supporting archives will open new discoveries. Here we focus on exploration for stars and stellar evolution
Increasing the Discovery Space in Astrophysics The Exploration Question for Planetary Systems, by Giuseppina Fabbiano, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c..86F/abstract Exploration can be the central question for Astro2020. Major astronomical discoveries were not driven by known questions, but by increasing discovery space via new telescopes and instruments, & now archive mining. Revolutionary facilities and supporting archives will open new discoveries. Here we focus on exploration for planetary systems.
Increasing the Discovery Space in Astrophysics The Exploration Question for Galaxy Evolution, by Giuseppina Fabbiano, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c..87F/abstract Exploration can be the central question for Astro2020. Major astronomical discoveries were not driven by known questions, but by increasing discovery space via new telescopes and instruments, & now archive mining. Revolutionary facilities and supporting archives will open new discoveries. Here we focus on exploration for galaxy evolution.
Increasing the Discovery Space in Astrophysics The Exploration Question for Cosmology, by Giuseppina Fabbiano, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c..88F/abstract Exploration can be the central question for Astro2020. Major astronomical discoveries were not driven by known questions, but by increasing discovery space via new telescopes and instruments, & now archive mining. Revolutionary facilities and supporting archives will open new discoveries. Here we focus on exploration for cosmology.
Increasing the Discovery Space in Astrophysics The Exploration Question for Compact Objects, by Giuseppina Fabbiano, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c..89F/abstract Exploration can be the central question for Astro2020. Major astronomical discoveries were not driven by known questions, but by increasing discovery space via new telescopes and instruments, & now archive mining. Revolutionary facilities and supporting archives will open new discoveries. We focus on compact objects & multi-messenger exploration.
Solar System Satellites: Key Science Enabled by the ngVLA, by Katherine de Kleer, California Institute of Technology NASA ADS record: 2019BAAS...51c..90D/abstract The solar system's satellites include worlds with ongoing geological processes, complex atmospheric chemistry, and high astrobiological potential. Data at 1-100 GHz with high spatial resolution and sensitivity such as the ngVLA will provide would significantly advance our understanding of these bodies' atmospheres and surface-interior exchange.
The Sun-like Stars Opportunity, by Giada Arney, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c..91A/abstract We describe how terrestrial planets in the habitable zones of Sun-like stars (i.e. FGK dwarfs) offer the best chance of discovering planets with conditions and evolutionary histories analogous to Earth's, as well as the best opportunity to detect unambiguous biosignatures.
Multi-Physics of AGN Jets in the Multi-Messenger Era, by Bindu Rani, NASA Goddard Space Flight Center, USA NASA ADS record: 2019BAAS...51c..92R/abstract This new era of multi-messenger astronomy, which will mature in the next decade, offers us the unprecedented opportunity to combine more than one messenger to solve some long-standing puzzles of AGN jet physics. We advocate the support to future instruments with large effective areas, excellent timing resolution, and wide fields of view.
What is the nature and origin of the highest-energy particles in the universe?, by Fred Sarazin, Colorado School of Mines NASA ADS record: 2019BAAS...51c..93S/abstract This white paper defines the science questions to be answered in the next decade in the field of Ultra-High Energy Cosmic-Rays. Following a review of the recent experimental and theoretical advances in the field, the paper outlines strategies and requirements desirable for the design of future experiments.
Discovery of Cold Brown Dwarfs or Free-Floating Giant Planets Close to the Sun, by Sandy Leggett, Gemini Observatory Northern Operations NASA ADS record: 2019BAAS...51c..95L/abstract This White Paper describes the opportunities for discovery of Jupiter-mass objects with 300K atmospheres. The discovery and characterization of such cold objects is vital for understanding the low-mass terminus of the initial mass function and for optimizing the study of exoplanets by the next generation of telescopes, space probes and missions.
Dark Energy and Modified Gravity, by Anze Slosar, Broookhaven National Laboratory NASA ADS record: 2019BAAS...51c..97S/abstract A community umbrella white-paper official endorsed by all main experimental collaborations on the Dark Energy and Modified Gravity research in the coming decade.
Stellar Feedback in the ISM Revealed by Wide-Field Far-Infrared Spectral-Imaging, by Javier R. Goicoechea, CSIC, Madrid, Spain NASA ADS record: 2019BAAS...51c..99G/abstract Atomic and molecular far-IR ( ~30 to 350 microns) lines are the most sensitive probes of stellar feedback processes. They allow us to quantify the deposition and cycling of energy in the ISM. In this white paper we emphasize the need of a space telescope with wide-field spectral-imaging capabilities in the critical far-IR domain.
Prompt Emission Polarimetry of Gamma-Ray Bursts, by Mark McConnell, University of New Hampshire / Southwest Research Institute NASA ADS record: 2019BAAS...51c.100M/abstract Many aspects of astrophysical jets can be studied by measuring the polarization of the prompt emission from GRBs. Theoretical models show that a more complete understanding of the inner structure of GRBs, including the geometry and physical processes close to the central engine, can only be achieved by gamma-ray polarimetry.
Astrophysics and Cosmology with Line-Intensity Mapping, by Ely Kovetz, Ben-Gurion University NASA ADS record: 2019BAAS...51c.101K/abstract We discuss how Line-Intensity Mapping - an emerging technique to measure the spatial fluctuations in the integrated emission from spectral lines originating from many individually unresolved galaxies and the diffuse intergalactic medium - can uniquely address a list of major open questions in Galaxy Evolution and Cosmology and Fundamental Physics.
Accretion in Stellar-Mass Black Holes at High X-ray Spectral Resolution, by Jon Miller, University of Michigan NASA ADS record: 2019BAAS...51c.102M/abstract Accretion disks around stellar-mass black holes are optimal regimes in which to make observational tests of seminal theory that applies across the mass scale. High X-ray spectral resolution will enable the most incisive tests. This white paper briefly reviews the key ideas and examines three case studies.
Do Supermassive Black Hole Winds Impact Galaxy Evolution?, by Francesco Tombesi, University of Maryland, College Park NASA ADS record: 2019BAAS...51c.103T/abstract Powerful winds driven by SMBHs are likely the main mechanism through which SMBHs regulate their own growth and influence the host galaxy evolution. However, their origin and their capability to impact the large-scale environment are still highly debated. Fundamental results will come from high-energy and spatial resolution X-ray observatories.
Binaries Matter Everywhere: from Precision Calibrations to Re-Ionization and Gravitational Waves, by Hans-Walter Rix, Max Planck Institute for Astronomy, Heidelberg NASA ADS record: 2019BAAS...51c.104R/abstract Binary stars are pivotal for the coming decade, enabling our understanding of star-formation, stellar evolution, stellar death, supernovae, black hole formation, cosmic re-ionization, and gravitational wave events. The field needs time-domain surveys in photometry, astrometry and spectroscopy. The first two exist, the last not (yet)!
The Need for Infrared Astrometry of Brown Dwarfs in the Post-Gaia Era, by J.Davy Kirkpatrick, Caltech/IPAC NASA ADS record: 2019BAAS...51c.105K/abstract Brown dwarf research in the next decade will be reliant on extending high-precision astrometry in wavelength and temporal coverage. Future astrometry will enable measures of the low-mass cutoff of star formation, allow for the discovery of cold brown dwarf analogs to cold (exo)planets, and enable mass measurements for single and binary systems .
The Promise of Data Science for the Technosignatures Field, by Anamaria Berea, University of Central Florida NASA ADS record: 2019BAAS...51c.106B/abstract This paper outlines some of the possible advancements for the technosignatures searches using the new methods currently rapidly developing in computer science, such as machine learning and deep learning, as well as a couple of case studies of large research programs where such methods have been already successfully implemented with notable results.
Primordial Non-Gaussianity, by Pieter Daniel Meeburg, Kavli Institute for Cosmology, Cambridge, UK, CB3 0HA NASA ADS record: 2019BAAS...51c.107M/abstract The aim of this white paper is to motivate the search for primordial non-Gaussianities in cosmology. Non-Gaussianities provide a unique opportunity to explore physics at the highest energy scales. We highlight recent theoretical advances, which predict new forms of non-Gaussianity and identify promising observational avenues.
Opportunities in Time-domain Stellar Astrophysics with the NASA Near-Earth Object Camera (NEOCam), by J. Davy Kirkpatrick, Caltech/IPAC NASA ADS record: 2019BAAS...51c.108K/abstract NEOCam will provide valuable data for the discovery and characterization of cold brown dwarfs, exoplanet analogs with weather variations, pre-main sequence variables, infrared-only transients, and more. For a relatively small investment, NASA can realize the full potential of NEOCam data by providing additional data products and transient alerting.
Synoptic Studies of the Sun as a Key to Understanding Stellar Astrospheres, by Valentin Martinez Pillet, National SOlar Observatory NASA ADS record: 2019BAAS...51c.110M/abstract Ground-based solar observations provide key contextual data (i.e., the “big pictureâ€) to produce a complete description of the only astrosphere we can study in situ: our Sun's heliosphere. This white paper outlines the current paradigm for ground-based solar synoptic observations, and indicates those areas that will benefit from focused attention.
D/H Ratio in Water and the Origin of Earth's Oceans, by Dariusz Lis, Caltech NASA ADS record: 2019BAAS...51c.111L/abstract Measurements of the D/H ratio in cometary water provide key constraints on the origin and history of water, and the contribution of comets to Earth's oceans. Measurement of the D/H ratio in a statistically significant sample of comets is as a high-priority goal for the next decade, important for understanding Earth's habitability.
X-ray follow-up of extragalactic transients, by Erin Kara, University of Maryland, NASA GSFC, MIT NASA ADS record: 2019BAAS...51c.112K/abstract Most violent and energetic processes in our universe, including mergers of compact objects, explosions of massive stars and extreme accretion events, produce copious amounts of X-rays. We identify key questions about several extragalactic multi-messenger and multi-wavelength transients, and demonstrate how X-ray followup answers these questions.
High-Energy Photon and Particle Effects on Exoplanet Atmospheres and Habitability, by Jeremy Drake, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c.113D/abstract Energetic stellar photon and particle radiation evaporates and erodes planetary atmospheres and controls upper atmospheric chemistry. Understanding of exoplanet atmospheres, their evolution and determination of habitability requires a powerful high-resolution X-ray imaging and spectroscopic observatory to characterize stellar energetic radiation.
The End of Galaxy Surveys, by Jason Rhodes, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.114R/abstract We advocate for defining a path to end the era of galaxy surveys by making the definitive measurements of the galaxy population in the optical/NIR, thereby creating a map of galaxies (and their associated dark matter) throughout the entire visible universe.
Where are the pevatrons?, by Pierre Cristofari, Gran Sasso Science Institute NASA ADS record: 2019BAAS...51c.115C/abstract The search for cosmic particle accelerators capable of reaching the PeV range, PeVatrons, is a crucial science target of the very-high-energy community. Such accelerators are essential in the context of the problem of the origin of Galactic cosmic rays, and in order to understand the mechanisms involved in the production of PeV particles.
Detecting the Birth of Supermassive Black Holes Formed from Heavy Seeds, by Fabio Pacucci, Kapteyn Astronomical Institute, Yale University NASA ADS record: 2019BAAS...51c.117P/abstract We investigate the capabilities required to study supermassive black holes formed by heavy seeds in the early Universe. We show that detecting heavy seeds at z>10 in the next decade will be feasible with upcoming and/or proposed facilities. Their detection will be fundamental to understand the early history of the Universe and its evolution.
All-Sky Near Infrared Space Astrometry, by Barbara McArthur, University of Texas at Austin NASA ADS record: 2019BAAS...51c.118M/abstract An all-sky near infrared (NIR) space observatory operating in the optical NIR, separated in time from the original Gaia would provide microarcsecond NIR astrometry and millimag photometry to penetrate obscured regions unraveling the internal dynamics of the Galaxy.
Structure of terrestrial planets and ocean worlds, by Jean-Luc Margot, University of California, Los Angeles NASA ADS record: 2019BAAS...51c.120M/abstract Rotation studies provide a unique window on the interior structure of planetary bodies. The science can be accomplished only with facilities that enable many other astronomical observations. The Astro2020 decadal survey will make recommendations about the facilities that are critical to the realization of the science described in this white paper.
The First Luminous Quasars and Their Host Galaxies, by Xiaohui Fan, University of Arizona NASA ADS record: 2019BAAS...51c.121F/abstract High-Redshift quasars probe the growth of early supermassive black holes (SMBHs) in the universe. In the next decade, new observations will push the frontier to the first luminous quasars at z>9, probe fainter quasar populations that trace earlier phases of BH growth, and connect SMBH growth with the rise of the earliest massive galaxies.
Core-Collapse Supernovae and Multi-Messenger Astronomy, by Chris Fryer, Los Alamos National Laboratory NASA ADS record: 2019BAAS...51c.122F/abstract Multi-messenger diagnostics for core-collapse supernovae span a wide range of diagnostics including observations across the entire electromagnetic spectrum, neutrinos, cosmic rays, dust grains and, in the future, gravitational waves. With next generation detectors, these multimessenger signals will probe all aspects of these energetic phenomena.
A High-resolution SZ View of the Warm-Hot Universe, by Tony Mroczkowski, European Southern Observatory (ESO) NASA ADS record: 2019BAAS...51c.124M/abstract We outline advances in the understanding of thermodynamic/kinematic properties of the warm-hot universe that can come through resolved measurements of the Sunyaev Zeldovich effects. Many advances will be enabled by new (sub)millimeter instrumentation on existing facilities, but truly transformative advances will require new mm/submm facilities.
Emission Line Mapping of the Circumgalactic Medium of Nearby Galaxies, by Dennis Zaritsky, University of Arizona NASA ADS record: 2019BAAS...51c.127Z/abstract The circumgalactic medium (CGM) is both the reservoir of gas for subsequent star formation and the depository of chemically processed gas, energy, and angular momentum from feedback. We discuss the opportunity to realize spectral-line images of the CGM in individual nearby galaxies. Such work will happen in the next decade.
Planet formation – The case for large efforts on the computational side, by Wladimir Lyra, California State University, Northridge NASA ADS record: 2019BAAS...51c.129L/abstract As advances are expected with ground based interferometers and the James Webb Space Telescope in the next decade, the central point of this white paper is what efforts on the computational side are required in the next decade to advance our theoretical understanding, explain the observational data, and guide new observations?
On the Use of Planetary Science Data for Studying Extrasolar Planets, by Daniel Crichton, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.130C/abstract There is an opportunity to advance solar system and extrasolar planetary studies that does not require new telescopes or new missions but better use and access to data sets. This approach leverages significant investment from space agencies in exploring the solar system and using those discoveries for the study of extrasolar planets.
High-Energy Galactic Cosmic Rays, by Frank Schroeder, Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, DE, USA NASA ADS record: 2019BAAS...51c.131S/abstract The origin of the highest energy Galactic cosmic rays is still not understood, nor is the transition to EeV extragalactic particles. Scientific progress requires enhancements of existing air-shower arrays, such as: IceCube with its surface detector IceTop, and the low-energy extensions of both the Telescope Array and the Pierre Auger Observatory.
Space-Based Gravitational Wave Observations in the Mid-Band Frequency Region, by Massimo Tinto, University of California San Diego, Center for Astrophysics and Space Sciences NASA ADS record: 2019BAAS...51c.133T/abstract The opportunity exists to scientifically explore the Gravitation Wave (GW) frequency band that is in between those accessible by LISA and LIGO. This frequency region could be accessible by a low-cost space-based interferometric detector that relies only on laser interferometry technology similar to that flown onboard the GRACE Follow-On mission.
Cosmological Probes of Dark Matter Interactions: The Next Decade, by Vera Gluscevic, University of Florida NASA ADS record: 2019BAAS...51c.134G/abstract We discuss observational and theoretical advancements that will play pivotal roles in realizing a strong program of cosmological searches for the fundamental nature of dark matter in the coming decade. We focus on next-generation measurements of the CMB anisotropy and spectral distortions, Ly-alpha forest, galaxies, and cosmological 21-cm signals.
Magnetic Fields of Extrasolar Planets: Planetary Interiors and Habitability, by Joseph Lazio, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.135L/abstract Generated by internal dynamos, magnetic fields are one of the few remote sensing means of constraining the properties of planetary interiors. The Earth's magnetic field has been speculated to be partially responsible for its habitability, and knowledge of an extrasolar planet's magnetic field may be necessary to assess its habitability.
The astrophysical r-process and the origin of the heaviest elements, by Ian Roederer, University of Michigan NASA ADS record: 2019BAAS...51c.136R/abstract The r-process is responsible for production of the heaviest elements, but many open questions remain about its nature. To answer these questions requires meaningful public access to high-resolution, UV/blue/optical spectroscopic instruments on 6-10 m telescopes, 30 m ELTs, and the next generation of space UV facilities.
HII Regions and the Warm Ionized Medium, by Loren Anderson, West Virginia University NASA ADS record: 2019BAAS...51c.137A/abstract Plasma of temperature 10,000K is created by OB stars and takes the form of discrete HII regions and diffuse gas. It is the key to determining the impact of massive stars on the interstellar medium (ISM) and the lifecycle of ISM gas. We review research this plasma, highlight outstanding questions, and provide recommendations for future facilities.
Tracing the feeding and feedback of active galaxies, by Enrique Lopez-Rodriguez, SOFIA Science Center / NASA AMES Center NASA ADS record: 2019BAAS...51c.138L/abstract Active galaxies accrete mass from their surroundings, and inject energy and mass to the galactic medium through outflows. The interface between the active galaxy and host galaxy is a region of a few pc in size with a gas and dust flow cycle. In the coming decade, we will demonstrate more directly the active role of the torus in galaxy evolution.
Extragalactic Proper Motions: Gravitational Waves and Cosmology, by Jeremy Darling, University of Colorado NASA ADS record: 2019BAAS...51c.139D/abstract We review the cosmological and local phenomena revealed by correlated extragalactic proper motions, their expected amplitudes, the current best measurements (if any), and predictions for Gaia. We describe key ground- and space-based observational requirements to measure or constrain these proper motion signals at the level of 100 nanoarcsec/year.
Synergies Between Galaxy Surveys and Reionization Measurements, by Steven Furlanetto, University of California Los Angeles NASA ADS record: 2019BAAS...51c.142F/abstract The epoch of reionization is one of the most exciting frontiers in astrophysics. Here we describe how the combination of galaxy surveys and direct 21-cm measurements of reionization can illuminate numerous mysteries of this fascinating era.
Resolving Galaxy Formation at Cosmic Noon, by Andrew Newman, Carnegie Institution for Science NASA ADS record: 2019BAAS...51c.145N/abstract We describe opportunities to transform our view of galaxy evolution at Cosmic Noon (z~2) by spatially resolving both early galaxies and their surrounding gaseous media using the angular resolution and sensitivity uniquely afforded by extremely large telescopes.
The Need for Laboratory Measurements and Ab Initio Studies to Aid Understanding of Exoplanetary Atmospheres, by Jonathan Fortney, University of California, Santa Cruz NASA ADS record: 2019astro2020T.146F/abstract We are now in the new era of the characterization of exoplanet atmospheres. However, atmosphere models are often limited by insufficiencies in the laboratory and theoretical data that serve as critical inputs. Here we provide descriptions of areas where new investigations could fill critical gaps in our ability to model exoplanet atmospheres.
A Formaldehyde Deep Field, by Jeremy Darling, University of Colorado NASA ADS record: 2019BAAS...51c.147D/abstract A formaldehyde deep field (FDF) can provide a blind, mass-limited survey of molecular gas across the history of star formation and galaxy evolution. We present a fiducial FDF that would span redshifts z = 0–7 and use formaldehyde line ratios to measure the molecular hydrogen number density for z > 0.45.
Using X-Ray Polarimetry to Probe the Physics of Black Holes and Neutron Stars, by Henric Krawczynski, Washington University in Saint Louis NASA ADS record: 2019BAAS...51c.150K/abstract This white paper highlights compact object and fundamental physics science opportunities afforded by high-throughput broadband (0.1-60 keV) X-ray polarization observations. The polarimetric observations can reveal the inner workings of high-energy sources, and allow us to test physical laws in the extreme conditions close to compact objects.
Cosmic Rays and interstellar medium with Gamma-Ray Observations at MeV Energies, by Elena Orlando, Kavli Institute for Particle Astrophysics and Cosmology and Hansen Experimental Physics Laboratory, Stanford University NASA ADS record: 2019BAAS...51c.151O/abstract We discuss the scientific prospects for studying cosmic rays and interstellar medium by observing gamma rays at MeV with unprecedented sensitivity and resolution. Low-energy cosmic rays and their sources, spectra all over the Galaxy, abundances, transport properties, and their role on the Galaxy evolution and star formation will be accessed.
Mass Spectroscopy of the Milky Way, by Arjun Dey, National Optical Astronomy Observatory NASA ADS record: Massively multiplexed spectroscopic surveys of Milky Way stars will revolutionize our understanding of our Galaxy's structural components, revealing their past history and the small-scale structure of its dark matter halo. A spectroscopic survey of 10^8 stars, previously unimaginable, is now within reach of new instruments in the coming decade.
Identification and characterization of the host stars in planetary microlensing with ELTs, by Chien-Hsiu Lee, NOAO NASA ADS record: 2019BAAS...51c.152L/abstract We propose to robustly and routinely measure the masses of exoplanets beyond 1 AU from their host stars with the microlensing method, by directly imaging the host star with ELTs. A direct result from this project will be planet occurrence rate beyond the snow line, which will enable us to discern different planet formation mechanisms.
Testing the Nature of Dark Matter with Extremely Large Telescopes, by Joshua Simon, Carnegie Observatories NASA ADS record: 2019BAAS...51c.153S/abstract Extremely large telescopes can critically test the predictions of the LambdaCDM model on small scales via the three-dimensional motions of stars in dwarf galaxies and integral field spectroscopy of gravitationally lensed galaxies and quasars. Such observations will conclusively determine whether dark matter is cold and collisionless.
Picturing a Panchromatic Past and Future, by Sara Price, Harvard-Smithsonian Center for Astrophysics NASA ADS record: 2019BAAS...51c.155P/abstract This white paper sets forth a few examples of impressive multi-wavelength discoveries by the Great Observatories, taken from a comprehensive analysis of Chandra press and image releases, in order to argue for a similar panchromatic approach in planning for future missions.
Exploring Active Supermassive Black Holes at 100 Micro-arcsecond Resolution, by Makoto Kishimoto, Kyoto Sangyo University NASA ADS record: 2019BAAS...51c.156K/abstract Super-high spatial resolution observations in the infrared are now enabling major advances in our understanding of supermassive black hole systems at the centers of galaxies. We describe the discovery potential of the current and future long-baseline interferometry in the infrared in this field.
Atmospheric disequilibrium as an exoplanet biosignature: Opportunities for next generation telescopes, by Joshua Krissansen-Totton, University of Washington NASA ADS record: 2019BAAS...51c.158K/abstract We explore atmospheric chemical disequilibrium as an exoplanet biosignature and argue that a CH4+CO2 combination could be a common sign of life on planets with oxygen-free atmospheres such as the ancient Earth. This biosignature combination is potentially detectable with JWST and readily detectable with some next generation space-based telescopes.
Messengers from the Early Universe: Cosmic Neutrinos and Other Light Relics, by Daniel Green, University of California San Diego NASA ADS record: 2019BAAS...51c.159G/abstract Measurements of the radiation density of the universe offer a broad window into both cosmic history and particle physics. Future cosmological observations, in particular of the cosmic microwave background, could reach clear observational targets that would lead to insights into nature and our universe that cannot be obtained by any other means.
Mapping Gas Phase Abundances and Enrichment Patterns Across Galaxy Disks, by Kathryn Kreckel, Max Planck Institute for Astronomy NASA ADS record: 2019BAAS...51c.161K/abstract In the coming decade we will map abundances of 1000s of HII regions within galaxies. This will allow us to understand the role of feedback and turbulence in driving the mixing and diffusion of metals in the ISM, search for over- and under-enriched regions, and resolve systematic uncertainties plaguing nebular abundance diagnostics.
The First Stars and the Origin of the Elements, by Ian Roederer, University of Michigan NASA ADS record: 2019BAAS...51c.163R/abstract No metal-free "first stars" have yet been found. We describe a survey strategy that could find one or more such stars or exclude their existence at reasonable confidence. This survey would leverage unique aspects of a two-hemisphere US-ELT system to characterize the nature of the elusive generation of first stars.
Astrochemical Origins of Planetary Systems, by Karin Oberg, Harvard University NASA ADS record: White paper outlines the chemical processes that regulate and affect the outcome of planet formation, and makes recommendations on future observatories and laboratory and theory support needed to address outstanding questions.
Astrochemical Origins of Planetary Systems, by Karin Oberg, Harvard University NASA ADS record: 2019BAAS...51c.165O/abstract White paper outlines the chemical processes that regulate and affect the outcome of planet formation, and makes recommendations on future observatories and laboratory and theory support needed to address outstanding questions.
Local Dwarf Galaxy Archaeology, by Alexander Ji, Carnegie Observatories NASA ADS record: 2019BAAS...51c.166J/abstract Local dwarf galaxies retain a record of high-redshift and metal-poor stellar populations. Resolved stellar spectroscopy provides insights into the first stars and galaxies, the smallest dark matter halos, and the first stellar explosions. ELTs with multi-object R=5k-30k spectroscopy will enable such studies for galaxies throughout the Local Group.
Understanding the evolution of close white dwarf binaries, by Odette Toloza, University of Warwick NASA ADS record: 2019BAAS...51c.168T/abstract In this white paper we stressed the importance of ultraviolet (high-resolution) and optical (low- and high-) spectroscopy to understand of evolution of close binaries that contain white dwarfs which lead to a variety of outcomes.
Evolved Planetary Systems around White Dwarfs, by Boris Gaensicke, University of Warwick NASA ADS record: 2019BAAS...51c.170G/abstract This white paper describes an ambitious research programme into the architectures of evolved planetary systems and their use as probes of the bulk abundances of exo-planetesimals, and we identify the facilities required over the next decade to reach our scientific goals.
Quasar absorption lines as astrophysical probes of fundamental physics and cosmology, by Hadi Rahmani, Paris Observatory NASA ADS record: 2019astro2020T.172R/abstract Quasar absorption lines provide unique tools to probe fundamental physics over cosmological scales. In this WP, we discuss the current open questions in the modern cosmology that can be answered, uniquely, using such absorption lines. We emphasise the essential role of a future high spectral resolution UV spectrograph in space, like LUVOIR/POLLUX.
Science at the edges:\ internal kinematics of globular clusters' external fields, by Andrea Bellini, Space Telescope Science Institute NASA ADS record: 2019astro2020T.173B/abstract The outer regions of globular clusters (GCs) can enable us to answer many fundamental questions. The outskirts of GCs are still uncharted territories observationally. A very efficient way to explore them is through high-precision proper motions of low-mass stars over a large field of view. To do this, WFIRST represents the best observational tool.
Observing Planetary Systems in the Making, by Andrea Isella, Rice University NASA ADS record: 2019BAAS...51c.174I/abstract We discuss science cases to support the development of sub-au imaging capabilities to image forming planets in the terrestrial region of nearby proto-planetary disks.
Where are the Intermediate Mass Black Holes?, by Jillian Bellovary, CUNY - Queensborough Community College and American Museum of Natural History NASA ADS record: 2019BAAS...51c.175B/abstract Observational evidence has been mounting for the existence of IMBHs, but constraining their masses is very challenging. IMBHs likely exist in dwarf galaxies, as well as wandering in massive galaxy halos. LISA will demystify IMBHs by detecting their mergers out to extremely high redshifts while measuring their masses with extremely high precision.
Solar System Ice Giants: Exoplanets in our Backyard., by Abigail Rymer, JHUAPL NASA ADS record: 2019BAAS...51c.176R/abstract Future exoplanet exploration can be enhanced by solar system exploration, here we focus on how analysis of solar system Ice Giants can provide enhanced science return to astrophysical measurements and solicit inclusion of specific wording supporting the astrophysical significance of an Ice Giant flagship-class mission in the Astro2020 report.
A New Era for X-ray Lensing Studies of Quasars and Galaxies, by George Chartas, College of Charleston NASA ADS record: 2019BAAS...51c.178C/abstract Gravitational lensing can be used to infer the structure near black holes, constrain the dynamics and evolution of black-hole accretion and outflows, test general relativity and constrain the evolution of dark matter in galaxies. These science goals can be reached with a next generation sub-arcsec and high-throughput X-ray telescope.
Characterizing the Distribution of Parameters of Planets Found by Radial Velocity is Essential for Understanding Planet Formation and Evolution, by Stuart F. Taylor, Participation Worldscope NASA ADS record: 2019BAAS...51c.179T/abstract Features in the distribution of exoplanet parameters by period demonstrate that the distribution of planet parameters is rich with infomation that can provide essential guidance to understanding the evolution of planetary systems. Structure that depends on the star's metallicity has been found in the counts of planets by log period. Eccentricity has correlations with planet number, metallicity, aggregate planet count density per log period, stellar multiplicity, and planet mass.
Tracing the formation history of galaxy clusters into the epoch of reionization, by Roderik Overzier, Observatório Nacional / Institute of Astronomy, Geophysics and Atmospheric Sciences, University of São Paulo NASA ADS record: 2019BAAS...51c.180O/abstract Protoclusters at z>2 are the sites of cluster formation. Deep, wide surveys are now delivering large numbers of these structures, allowing us to trace the origin of galaxy clusters into the epoch of reionization. Here we review our current understanding of the field with an emphasis on the next generation of large aperture telescopes.
Deciphering the Protostellar Disk Evolution Recorded by Cometary Deuterated Water, by Bjorn Davidsson, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.182D/abstract We propose intensified efforts to determine the deuterium abundance in comet water for a large number of objects, and to use this information to better understand the physical and chemical evolution of protostars during their collapse phase.
Prospects for the detection of synchrotron halos around middle-age pulsars, by Mattia Di Mauro, NASA's Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.183D/abstract Cosmic-ray positrons emitted by PWNe can produce photons, distributed in halos, at X-ray energies through synchrotron radiation. In this white paper we show that mission concepts, such as AMEGO AdEPT, are suitable to detect these synchrotron halos and we will report the list of the most promising PWNe that could be able to detect.
Astrophysics Uniquely Enabled by Observations of High-Energy Cosmic Neutrinos, by Abigail Vieregg, University of Chicago NASA ADS record: 2019BAAS...51c.185V/abstract This white paper describes the outstanding astrophysics questions that neutrino astronomy can address in the coming decade. Detailed measurements of the diffuse neutrino flux, neutrinos from point sources, and multi-messenger observations with neutrinos will enable the discovery and characterization of the most energetic sources in the Universe.
Compact Stellar Jets, by Thomas Maccarone, Texas Tech University NASA ADS record: 2019BAAS...51c.186M/abstract Jets produced by compact stars are the ideal laboratories for understanding jets in general due to the ability to measure accretors properties accurately, and the short timescales of variability of the systems. We outline what is needed to move forward with understanding jet production in X-ray binaries.
The Formation and Evolution of Multiple Star Systems, by John Tobin, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.187T/abstract Multiple star systems are a frequent outcome of the star formation process and their formation must be studied in the protostellar phase. We review the new directions of research that can be taken in the next decade with current and new facilities, specifically those operating in the millimeter/centimeter radio wavelength range.
A Summary of Multimessenger Science with Galactic Binaries, by Thomas Kupfer, Kavli Insitute for Theoretical Physics / UC Santa Barbara NASA ADS record: 2019BAAS...51c.188K/abstract Galactic binaries with orbital periods less than ≈1hr are strong gravitational wave sources in the mHz regime, ideal for LISA. In this white paper we present an overview of the opportunities for research on Galactic binaries using multi-messenger observations and summarize some recommendations for the 2020 time-frame.
Measuring Protostar Masses: The Key to Protostellar Evolution, by John Tobin, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.189T/abstract Our understanding of the early evolution of protostars is limited by our lack mass measurements for the protostellar objects. The masses of protostars can only be directly measured using millimeter interferometry to observe spectral lines from the rotating disks and infalling envelopes, requiring large investments of time and/or facility upgrades.
The Sun at GeV--TeV Energies: A New Laboratory for Astroparticle Physics, by Mehr Nisa, University of Rochester NASA ADS record: 2019BAAS...51c.194N/abstract We discuss the unresolved puzzles in our understanding of the very-high-energy Sun from the standpoint of particle astrophysics, current and future observations of the Sun in gamma rays and neutrinos, and their significance for probing fundamental questions in cosmic-ray propagation, dark matter searches and multi-messenger astronomy.
First Stars and Black Holes at Cosmic Dawn with Redshifted 21-cm Observations, by Jordan Mirocha, McGill University NASA ADS record: 2019BAAS...51c.195M/abstract Though difficult to detect directly, the first stars and black holes forming during the "cosmic dawn" can be constrained indirectly through the 21-cm background, which traces the properties of intergalactic hydrogen gas. In this white paper, we focus on the science enabled by low-frequency radio observations of the 10 < z < 30 epoch.
Pulsation as a Laboratory for Understanding Stellar Physics, by Michelle Creech-Eakman, New Mexico Institue of Mining and Technology NASA ADS record: 2019BAAS...51c.196C/abstract This paper presents a review of stellar pulsation across the H-R diagram and the critical importance of pulsation investigations in order to make important inroads into understanding fundamental processes in stellar physics. This area of astrophysics has been largely overlooked by the community and is ripe for new discoveries over the next Decade.
Fundamental Stellar Physics throughout the Galaxy, by Derek Buzasi, Florida Gulf Coast University NASA ADS record: 2019BAAS...51c.197B/abstract Our understanding of stars is fundamental to our understanding of topics from circumstellar disks and exoplanets to the life history of galaxies, cosmological distance scales, and primordial nucleosynthesis. Spectroscopy and high-spatial resolution imaging can revolutionize open cluster studies by targeting the faintest stars in open clusters.
Gravity-wave asteroseismology of intermediate- and high-mass stars, by Andrew Tkachenko, Institute of Astronomy, KU Leuven NASA ADS record: 2019BAAS...51c.198T/abstract This white paper focuses specifically on the transport of chemical elements and of angular momentum in the stellar structure and evolution models of stars born with convective core, as revealed by their gravity-mode oscillations.
Spatially Resolved UV Nebular Diagnostics in Star-Forming Galaxies, by Bethan James, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.199J/abstract This paper describes the need for spatially resolved rest-frame UV spectroscopy across nearby SFGs via a space-based UV-IFU. Such observations will robustly constrain the diagnostic tools critical to understanding fundamental questions concerning the evolution, physical conditions, and ionization structure of SFGs across cosmic time.
Cosmological Synergies Enabled by Joint Analysis of Multi-probe data from WFIRST, Euclid, and LSST, by Jason Rhodes, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.201R/abstract WFIRST, Euclid, and LSST are all missions designed to perform dedicated cosmology surveys that offer unprecedented statistical constraining power and control of systematic uncertainties. There is a growing realization that these missions will be significantly more powerful when the data are processed and analyzed in unison.
Searching for Sources of TeV Particle Dark Matter in the Southern Hemisphere, by Andrea Albert, Los Alamos National Lab NASA ADS record: 2019BAAS...51c.202A/abstract Many promising models hypothesize that dark matter is a particle that can annihilate or decay and produce secondary gamma rays. The Southern Hemisphere is home to many key dark matter targets. A wide field of view survey observatory is needed to probe the many dark matter targets in the Southern Hemisphere.
Exploring Frontiers in Physics with Very-High-Energy Gamma Rays, by Reshmi Mukherjee, Barnard College, Columbia University NASA ADS record: 2019BAAS...51c.203M/abstract This white paper briefly summarizes what can be learned over the coming decade in studies of fundamental physics through ground-based gamma-ray observations over the 20 GeV to 300 TeV range. The superior sensitivity and energy coverage of next generation instruments such as CTA will allow unprecedented exploration of the frontiers of physics.
Mapping Ultracool Atmospheres: Time-domain Observations of Brown Dwarfs and Exoplanets, by Daniel Apai, University of Arizona NASA ADS record: 2019BAAS...51c.204A/abstract Ultracool atmospheres (brown dwarfs, directly imaged exoplanets, close-in and transiting gas giants) are at one of the forefronts of modern astrophysics. We describe the key challenges to understanding ultracool atmospheres and the importance of time-domain observations (indirect spatial information) to address these challenges.
Far-Infrared studies of Star and Planet Formation, by James Jackson, USRA NASA ADS record: 2019BAAS...51c.205J/abstract Far-infrared observations of star-forming regions trace the star-forming material density and temperature as well as the shape of the magnetic field (through polarization of dust thermal continuum). Far-infrared spectroscopy of disks around young stars can reveal the initial conditions of planet formation.
Stellar multiplicity: an interdisciplinary nexus, by Adrian Price-Whelan, Princeton University NASA ADS record: 2019BAAS...51c.206P/abstract This white paper emphasizes the interdisciplinary importance of binary-star science and advocates that coordinated investment in understanding stellar multiplicity from all astrophysical communities will benefit almost all branches of astrophysics.
Dark Matter Science in the Era of LSST, by Keith Bechtol, University of Wisconsin-Madison NASA ADS record: 2019BAAS...51c.207B/abstract We summarize astrophysical observations that can constrain the fundamental physics of dark matter in the era of LSST. We highlight theoretical work and observational facilities that will complement LSST. Astrophysical observations will guide other experimental efforts while probing unique regions of dark matter parameter space.
Sunyaev Zel'dovich study of filamentary structures between galaxy clusters, by Elia Stefano Battistelli, Physics department, Sapienza, University of Rome, Italy NASA ADS record: 2019BAAS...51c.208B/abstract The Sunyaev Zel'dovich effect measurement of the inter-cluster region between galaxy clusters would be fundamental for the study of filamentary structures and missing baryons in our Universe. We argue that a bolometric camera observing at ∼3mm coupled to a 50−100m class radio telescope is the ideal instrument to disentangle different scenarios.
Radio Counterparts of Compact Object Mergers in the Era of Gravitational-Wave Astronomy, by Alessandra Corsi, Texas Tech University NASA ADS record: 2019BAAS...51c.209C/abstract GHz radio astronomy has played a fundamental role in the multi-messenger discovery of the binary neutron star merger GW170817. We show how the projected increase in sensitivity of gravitational-wave detectors over the next decade dramatically calls for an improvement in both sensitivity and spatial resolution on current U.S.-based radio arrays.
Probing Macro-Scale Gas Motions and Turbulence in Diffuse Cosmic Plasmas, by Esra Bulbul, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c.210B/abstract Cluster outskirts provide crucial information on the assembly and virialisation processes of massive dark matter haloes and cosmology. This paper provide future prospects for measurements thermodynamic and kinematic properties of the intracluster medium in faint regions of galaxy clusters with forthcoming planned X-ray and SZ observatories.
‘Auxiliary' Science with the WFIRST Microlensing Survey, by B. Scott Gaudi, The Ohio State University NASA ADS record: 2019BAAS...51c.211G/abstract The WFIRST Microlensing Survey will enable the measurement of the compact object mass function over ten orders of magnitude, the detection of ~100,000 Transiting Planets, astroseismology of ~1,000,000 bulge giants, the detection of ~5000 trans-Neptunian objects, and measurement of parallaxes and proper motions of ~6,000,000 bulge and disk stars.
Taking Census of Massive, Star-Forming Galaxies formed <1 Gyr After the Big Bang, by Caitlin Casey, University of Texas at Austin NASA ADS record: 2019BAAS...51c.212C/abstract This concept paper focuses on strategies for finding and characterizing such early Universe (z > 3) dusty star-forming galaxies (DSFGs), with particular focus on pushing toward higher redshifts when DSFG formation scenarios place more stringent constraints on the formation of the earliest massive galaxies, <1 Gyr after the Big Bang.
Fundamental Physics with Brown Dwarfs: The Mass-Radius Relation, by Adam Burgasser, UC San Diego NASA ADS record: 2019BAAS...51c.214B/abstract The lowest-mass stars, brown dwarfs and giant exoplanets span a minimum in the mass-radius relationship that probes the fundamental physics of extreme states of matter, magnetism, and fusion. This White Paper outlines scientific opportunities and the necessary resources for modeling and measuring the mass-radius relationship in this regime.
Fundamental Physics with High-Energy Cosmic Neutrinos, by Abigail Vieregg, University of Chicago NASA ADS record: 2019BAAS...51c.215V/abstract This white paper describes the outstanding particle physics questions that high-energy cosmic neutrinos can address in the coming decade. Tests of fundamental physics using high-energy cosmic neutrinos will be enabled by detailed measurements of their energy spectrum, arrival directions, flavor composition, and timing.
Ultra-heavy cosmic-ray science: Are r-process nuclei in the cosmic rays produced in supernovae or binary neutron star mergers?, by Walter Binns, Washington University in St. Louis NASA ADS record: Galactic cosmic rays play an important role in the dynamics of matter and magnetic fields in the interstellar medium, and probably also in star formation. There is an opportunity during the coming decade to answer these questions by measuring the relative abundances of every individual element heavier than iron, including the actinides.
Far-Infrared studies of Galaxy Evolution, by William Reach, USRA NASA ADS record: 2019BAAS...51c.216R/abstract Far-infrared observations trace galaxy evolution through dust thermal emission, including its polarization, and fine-structure lines from the gas. Galaxy evolution must be informed by properties of galaxies that can be resolved and physical mechanisms (heating, cooling, and magnetic field influence) witnessed.
Precision measurement of magnetic field from near to far, from fine to large scales in ISM, by Huirong Yan, DESY & University of Potsdam NASA ADS record: 2019BAAS...51c.217Y/abstract Spectropolarimetry from Ground State Alignment (GSA) has been suggested as a direct tracer of magnetic field in interstellar diffuse medium. It provides a unique tool for studies of sub-gauss magnetic fields using polarimetry of UV, optical and radio lines. Both 3D tomography and topology are achievable.
Unveiling the Galaxy Cluster - Cosmic Web Connection with X-ray observations in the Next Decade, by Stephen Walker, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.218W/abstract In recent years, the outskirts of galaxy clusters have emerged as one of the new frontiers and unique laboratories for studying the growth of large scale structure in the universe. A next-generation X-ray telescope is required in order to reveal the full story of the growth of galaxy clusters and the cosmic web and their applications for cosmology.
Stellar physics with high-resolution UV spectropolarimetry, by Coralie Neiner, LESIA, Paris Observatory, France NASA ADS record: 2019BAAS...51c.219N/abstract Current burning issues in stellar physics, for both hot and cool stars, concern their magnetism and its impact on stellar structure, evolution, activity, and circumstellar environment. However, the role of magnetism is complex and thus poorly understood as of today. It needs to be quantified with high-resolution UV spectropolarimetric measurements.
Galactic center star formation & feedback: key questions, by Adam Ginsburg, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.220G/abstract The closest galaxy center is a powerful laboratory for studying the secular processes that shape galaxies across cosmic time. Large-scale, high-resolution studies of this section of the Galaxy will connect Galactic star formation studies to extragalactic.
Unveiling the Phase Transition of the Universe During the Reionization Epoch with Lyman-alpha, by Steven Finkelstein, The University of Texas at Austin NASA ADS record: 2019BAAS...51c.221F/abstract The observation of Lyman-alpha emission from galaxies in the epoch of reionization (6 < z < 10) provides the best opportunity to obtain a detailed measurement of the temporal and spatial evolution of this phase change in the next decade. These observations require large (>20m) collecting areas to reach attenuated emission from faint galaxies.
The Disk Gas Mass and the Far-IR Revolution, by Edwin Bergin, University of Michigan NASA ADS record: 2019BAAS...51c.222B/abstract Planet formation is one of the major areas where significant growth is expected in the coming decade. A major missing piece is our lack of knowledge of the planet forming disk's gas mass. This white paper discusses how we can make a significant advance in this area and aid countless subsequent studies with grounding knowledge of the total mass.
Probing Galaxy Evolution through Far- Infrared Spectroscopy of the Interstellar Medium., by Jorge L. Pineda, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.223P/abstract In this white paper we lay out a roadmap that builds on the use of multi-scale, high-spectral resolution observations of far-infrared fine-structure lines, to study the physical processes governing the evolution of the interstellar medium in galaxies, and how they impact the regulation of star formation in galaxies.
Determining the Composition of Interstellar Dust with Far-Infrared Polarimetry, by Brandon Hensley, Princeton University NASA ADS record: 2019BAAS...51c.224H/abstract Does interstellar dust come in distinct silicate and carbonaceous varieties, or are interstellar grains a homogeneous mishmash of different materials? We argue that sensitive dust polarimetry from ~100-850um can provide a definitive test, with implications ranging from the evolution of metals in the ISM to component separation in CMB experiments.
Surveying the solar neighborhood for ozone in the UV at temperate rocky exoplanets, by Doug Lisman, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.225L/abstract This whitepaper shows ozone to be the best potential biosignature gas for an early exoplanet imaging mission. While oxygen is not detectable at Earth until about 0.5 Ga, its proxy ozone is detectable for about half of that history. Ozone's pronounced UV feature yields a small starshade and telescope and a simple photometer instrument.
Populations of Black holes in Binaries, by Thomas Maccarone, Texas Tech University NASA ADS record: 2019BAAS...51c.226M/abstract This paper outlines the importance of understanding the mass distributions, spin distributions, and natal kick distributions of compact objects, with an emphasis on black holes. It discusses means to improve sizes of source populations and understanding of key source parameters.
Dynamical Processes in the Planet-Forming Environment, by Peregrine McGehee, College of the Canyons NASA ADS record: 2019BAAS...51c.227M/abstract The transfer of circumstellar disk mass and momentum onto the protostar and out into the environment occurs via a variety of mechanisms including magnetospheric accretion, jets,outflows, and disk winds. Metallic emission lines, along with the Balmer series of hydrogen, probe the kinematics of gas within the planet-forming regions of the disks.
A Unique Messenger to Probe Active Galactic Nuclei: High-Energy Neutrinos, by Marcos Santander, University of Alabama NASA ADS record: 2019BAAS...51c.228S/abstract We advocate for a multi-messenger approach that combines high-energy neutrino and broad multi-wavelength electromagnetic observations to study AGN during the coming decade. The unique capabilities of these joint observations promise to solve several long-standing issues in our understanding of AGN as powerful cosmic accelerators.
The trail of water and the delivery of volatiles to habitable planets, by Klaus Pontoppidan, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.229P/abstract Water is fundamental to our understanding of the formation of planets and the delivery of volatiles to their surfaces. Yet, we currently have no facilities capable of comprehensively observing it. A cold, space-based observatory operating at 25-600 micron is needed to address fundamental questions about the origin of planets and their water.
A Shocking Shift in Paradigm for Classical Novae, by Laura Chomiuk, Michigan State University NASA ADS record: 2019BAAS...51c.230C/abstract The discovery of GeV gamma-rays from classical novae has led to a reassessment of these garden-variety explosions, and highlighted their importance for understanding radiative shocks, particle acceleration, and dust formation in more exotic, distant transients.
How Do Stars Form? Open Questions on the Stellar Initial Mass Function, by Daniela Calzetti, University of Massachusetts, Amherst NASA ADS record: 2019BAAS...51c.231C/abstract This WP summarizes the recent progress on observations and models of short timescale star formation and the IMF. The challenges ahead include the relation between cores and stars, the physical nature of the characteristic mass, the existence and nature of a high-mass limit for stars, and the environment effects on stellar multiplicity and the IMF.
Closing Gaps in Our Astrochemical Heritage: From Molecular Clouds to Planets, by Brett McGuire, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.234M/abstract We discuss the observational needs in the coming decade to enable the robust interpretation of chemical evolution from molecular clouds through to the formation of planets, especially in sources such as protoplanetary disks and exoplanet atmospheres, where only the simplest of species can be directly observed.
Science Opportunities with Long Baseline Radio Interferometry and Micro-arcsecond Astrometry, by Mark Reid, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c.235R/abstract Long Baseline Radio Interferometry can achieve the highest angular resolution in astronomy and has demostrated astrometric accuracy of ~10 microarcseconds. With increased sensitivity it can achieve ~1 microarcsecond accuracy, uniquely opening a wide range of astrophysical problems for study.
Revealing Chemical Evolution Throughout the Star-Formation Process, by Brett McGuire, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.236M/abstract We discuss the observational, modeling, and laboratory advances required to push our understanding of the evolution of the most complex, prebiotic chemistry in the ISM, including the potential cosmic origins of biological homochirality.
Multi-Messenger Astronomy with Extremely Large Telescopes, by Ryan Chornock, Ohio University NASA ADS record: 2019BAAS...51c.237C/abstract A key goal for Multi-Messenger Astronomy will be to characterize gravitational wave and neutrino sources using the next generation of Extremely Large Telescopes. These studies will have a broad impact across astrophysics. The counterparts to high-frequency GW sources will be distant and faint and thus demand ELT capabilities for characterization.
In Pursuit of Galactic Archaeology, by Melissa Ness, Columbia/Flatiron NASA ADS record: 2019BAAS...51c.238N/abstract The next decade affords tremendous opportunity to achieve the goals of Galactic archaeology. That is, to reconstruct the evolutionary narrative of the Milky Way, based on the empirical data that describes its current morphological, dynamical, temporal and chemical structures. Here, we describe the path to achieving this goal.
The Yet-unobserved Multi-Messenger Gravitational-Wave Universe, by Vassiliki Kalogera, Northwestern U. NASA ADS record: 2019BAAS...51c.239K/abstract Observations with next-generation ground-based detectors further enhanced with multi-messenger (electromagnetic and neutrino) detections will allow us to probe new extreme astrophysics. Target sources included: core-collapse supernovae, continuous emission from isolated or accreting neutron stars, and bursts from magnetars and other pulsars.
Impacts of Quantum Chemistry Calculations on Exoplanetary Science, Planetary Astronomy, and Astrophysics, by Der-you Kao, NASA Goddard Space Flight Center/ Universities Space Research Association NASA ADS record: 2019BAAS...51c.240K/abstract Quantum chemical simulations have matured enough to describe real systems with an accuracy that competes with experiments. Several existing quantum chemical studies supporting exoplanetary science are described, and the potential impacts of improved models associated with scientific goals of missions are addressed.
Cool, evolved stars: results, challenges, and promises for the next decade, by Gioia Rau, NASA/GSFC & CUA NASA ADS record: 2019BAAS...51c.241R/abstract This White Paper identifies compelling scientific opportunities in the field of Cool, Evolved Stars, describing the observational and theorical challenges to our understanding, and the key advancements made. We portray the pathway towards understanding, and identify, through recommendations, which advancements are necessary in 2020-2030 & beyond.
Deeper, Wider, Sharper: Next-Generation Ground-based Gravitational-Wave Observations of Binary Black Holes, by Vicky Kalogera, Northwestern U. NASA ADS record: 2019BAAS...51c.242K/abstract Next-generation observations will revolutionize our understanding of binary black holes and will detect new sources, such as intermediate-mass black holes. Primary science goals include: Discover binary black holes throughout the observable Universe; Reveal the fundamental properties of black holes; Uncover the seeds of supermassive black holes.
Resolving the Radio Photospheres of Main Sequence Stars, by Christopher Carilli, NRAO NASA ADS record: 2019BAAS...51c.243C/abstract We discuss the need for spatially resolved observations of the radio photospheres of main sequence stars. Such studies are fundamental to determining the structure of stars in the key transition region from the cooler optical photosphere to the hot chromosphere -- the regions powering exo-space weather phenomena.
Protostellar Disks: The Missing Link Between Cores and Planets, by Patrick Sheehan, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.244S/abstract A look at the studies and facilities needed to move forward our understanding of protostellar disks, which represent the initial conditions in disks after forming from cloud collapse but before planet formation has occurred.
The production and escape of ionizing photons from galaxies over cosmic time, by Jane Rigby, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.245R/abstract Ionizing photons produced by massive stars play a key role in galaxy evolution and in ending the dark ages. Fundamental unsolved questions about the production and escape of ionizing photons, and how ionizing galaxy populations evolve through cosmic time, can be definitively answered with next-gen UV spectroscopy, in concert with JWST and the ELTs.
Multi-messenger and transient astrophysics with very-high-energy gamma rays, by Justin Vandenbroucke, University of Wisconsin NASA ADS record: The discoveries of high-energy astrophysical neutrinos and of gravitational waves, as well as the rise of time-domain astronomy, have revolutionized astrophysics. We describe the prospects for gamma-ray telescopes, particularly in the energy range greater than 20 GeV, for multi-messenger and transient astrophysics in the decade ahead.
Polarization in Disks, by Ian Stephens, CfA/SAO NASA ADS record: 2019BAAS...51c.246S/abstract This white paper discusses how disk polarization observations can be used to study disk and grain properties during the planet formation process. Such studies require very sensitive and high resolution multi-wavelength observations.
AGN (and other) astrophysics with Gravitational Wave Events, by K. E. Saavik Ford, CUNY BMCC/Am. Museum of Natural History/CUNY GC NASA ADS record: 2019BAAS...51c.247F/abstract LIGO-detected stellar mass binary black hole (sBBH) mergers may be used to constrain key parameters of AGN disks. This is true even if AGN are not primarily responsible for driving sBBH mergers. We outline how to organize GW, EM, and neutrino observations to gather maximal astrophysical information on important drivers of galactic evolution.
COSMOLOGY AND THE EARLY UNIVERSE, by Bangalore Sathyaprakash, The Pennsylvania State University NASA ADS record: 2019BAAS...51c.248S/abstract This WP deals with what we might learn from future gravitational wave observations about the early universe phase transitions and their energy scales, primordial black holes, Hubble parameter, dark matter and dark energy, modified theories of gravity and extra dimensions.
How does dust escape from galaxies?, by Edmund Hodges-Kluck, University of Maryland/NASA GSFC NASA ADS record: 2019BAAS...51c.249H/abstract A large fraction of all the dust ever produced resides outside of the galaxies in which it was formed. Studies in the past decade broadly characterized the circumgalactic dust, but a study of outflowing or stripped dust around individual galaxies is needed to understand how it escapes. We discuss the prospects and requirements to do this.
Opportunities for Multimessenger Astronomy in the 2020s, by Eric Burns, NASA Goddard NASA ADS record: 2019BAAS...51c.250B/abstract We present an overview of multimessenger science and the capabilities necessary to enable them. In short, we recommend a broad range of instruments and missions, with improved communication. We end with a table demonstrating this need.
EXTREME GRAVITY AND FUNDAMENTAL PHYSICS, by Bangalore Sathyaprakash, The Pennsylvania State University NASA ADS record: 2019BAAS...51c.251S/abstract Future gravitational-wave observations will enable unprecedented and unique science in extreme gravity and fundamental physics answering questions about the nature of dynamical spacetimes, the nature of dark matter and the nature of compact objects.
Dark Matter Physics with Wide Field Spectroscopic Surveys, by Ting Li, Fermi National Accelerator Laboratory NASA ADS record: 2019BAAS...51c.252L/abstract This white paper summarizes the astronomical observations for next decade to probe the particle properties of dark matter, and concludes that a 10m class wide-field, high-multiplex spectroscopic survey facility is required for the next decade to definitively search for deviations from the cold collisionless dark matter model.
The L/T Transition, by Johanna Vos, American Museum of Natural History NASA ADS record: 2019BAAS...51c.253V/abstract The L/T transition is an important evolutionary phase in brown dwarf atmospheres. In the next decade, we will answer three key questions: 1. What is the physical mechanism behind the L/T transition? 2. What is the spatial extent of atmospheric structures at the L/T transition? 3. How do gravity and metallicity affect the L/T transition?
Far- to near-UV spectroscopy of the interstellar medium at very high resolution and very high signal-to-noise ratio, by Cecile Gry, Laboratoire d'Astrophysique de Marseille, Aix Marseille Univ. NASA ADS record: 2019BAAS...51c.254G/abstract A comprehensive study of the ISM phases and the nature of their connections requires comparing abundances and velocity profiles of tracers of the different phases. A wealth of absorption features from such tracers are found in the full UV domain that need to be observed at high resolving power R>200 000 and high signal-to-noise ratio SNR>500.
High velocity Clouds: Building Blocks of the Local Group?, by Felix Lockman, Green Bank Observatory NASA ADS record: 2019BAAS...51c.255L/abstract High velocity clouds (HVCs) are gaseous objects with unusual velocities that lie in the halo of the Milky Way and can be used to trace the exchange of gas between disk and halo, accretion of new gas, and tidal streams. IHVCs are key to understanding the relationship between Galactic disks and their halos.
Positron Annihilation in the Galaxy, by Carolyn Kierans, NASA/Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.256K/abstract The 511 keV line from positron annihilation in the Galaxy was detected ~50 years ago, but the source of positrons is still unconfirmed and remains one of the enduring mysteries in gamma-ray astronomy. We will summarize the current knowledge base of Galactic positrons, and discuss how next-generation instruments could finally provide the answers.
Hot Drivers of Stellar Feedback from 10 to 10,000 pc, by Edmund Hodges-Kluck, University of Maryland/NASA GSFC NASA ADS record: 2019BAAS...51c.257H/abstract Stellar feedback begins in individual star clusters but shapes entire galaxies. It operates in large part through work done by hot gas, but observational constraints on the nature of this gas remain poor on all scales, leading to major uncertainties in galaxy evolution models. We explore how new X-ray observations can make breakthrough progress.
Tracing the Origins and Evolution of Small Planets using Their Orbital Obliquities, by Marshall Johnson, The Ohio State University NASA ADS record: 2019BAAS...51c.258J/abstract We recommend an intensive effort to survey the orbital obliquity distribution of small close-in exoplanets over the coming decade. This is a key tracer of how planets form and migrate. Over the next decade we can observe hundred of planets as small as ~2 REarth, opening a window into the orbital properties of the most common planets.
MMA SAG: Thermonuclear Supernovae, by Michael Zingale, Stony Brook University NASA ADS record: 2019BAAS...51c.259Z/abstract Type Ia supernovae are important as sites of nucleosynthesis and as distance indicators. But remarkably, we still do not have a consensus on the underlying progenitor of these events. Multimessenger observations over the next decade will bring a wealth of new information about SN Ia, allowing us to uncover the origin and mechanism of these events.
Gamma Rays and Gravitational Waves, by Eric Burns, NASA Goddard NASA ADS record: 2019BAAS...51c.260B/abstract The first multimessenger detection of a neutron star merger was independently detected in gamma-rays and gravitational waves. The two messengers will jointly identify new sources in the next few years, beyond neutron star mergers. We present a summary of possible sources and discuss the capabilities needed to study them.
Radio Pulsar Populations, by Duncan Lorimer, West Virginia University NASA ADS record: 2019BAAS...51c.261L/abstract We provide an overview of the radio pulsar population as it is currently understood, and give predictions for surveys with predominantly large single-dish radio facilities over the coming decade. Over 10,000 pulsars are expected to be found. Applications include tests of gravity and as natural laboratories for low-frequency gravitational waves.
Probing Strong Binary Interactions and Accretion in Asymptotic Giant Branch Stars, by Raghvendra Sahai, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.262S/abstract Understanding strong binary interactions is of wide astrophysical importance, and the deaths of most stars in the Universe that evolve in a Hubble time (~1-8 Msun) could be fundamentally affected by such interactions. We outline the main scientific issues and how these can be addressed with upcoming facilities in the radio, UV and X-ray domains.
Future X-ray Studies of Supernova Remnants, by Brian Williams, NASA GSFC NASA ADS record: 2019BAAS...51c.263W/abstract This white paper outlines the progress that can be made from the next generation of X-ray telescopes in the study of the remnants of supernovae, both galactic and extragalactic. We primarily focus on high spectral resolution instruments and the science they will enable.
Astromineralogy of interstellar dust with X-ray spectroscopy, by Lia Corrales, University of Michigan NASA ADS record: 2019BAAS...51c.264C/abstract X-ray absorption fine structure (XAFS) in the 0.2-2 keV band is a crucial component in multi-wavelength studies of dust mineralogy, size, and shape. We discuss large open questions in astromineralogy and describe how planned and potential X-ray telescopes will play a key roll in answering those questions.
Probing Extreme Environments with Very-High-Energy Gamma Rays, by David Williams, University of California Santa Cruz NASA ADS record: 2019BAAS...51c.265W/abstract This white paper briefly summarizes what can be learned over the coming decade about extreme astrophysical environments through ground-based gamma-ray observations over the 20 GeV to 300 TeV range.
UV Diagnostics of Galaxies from the Peak of Star-Formation to the Epoch of Reionization, by Casey Papovich, Texas A&M University NASA ADS record: 2019BAAS...51c.266P/abstract We describe prospects facilitated by giant telescopes in the 2020s to use rest-frame UV spectroscopy to study the properties of massive stellar populations and gas (ionization, metallicity, kinematics, outflows) in and around galaxies from the peak of the cosmic star-formation density (z~3) up in to the epoch of reionization (z>6).
Understanding the Origin and Impact of Relativistic Cosmic Particles with Very-High-Energy Gamma-rays, by Jamie Holder, University of Delaware NASA ADS record: 2019BAAS...51c.267H/abstract This white paper briefly summarizes the importance of the study of relativistic cosmic rays, both as a constituent of our Universe, and through their impact on stellar and galactic evolution. The focus is on what can be learned over the coming decade through ground-based gamma-ray observations over the 20 GeV to 300 TeV range.
Ground-Based Radial Velocity as Critical Support for Future NASA Earth-Finding Missions, by Courtney Dressing, University of California, Berkeley NASA ADS record: 2019BAAS...51c.268D/abstract A precursor radial velocity (RV) survey would benefit direct imaging missions by (1) finding potentially habitable planets; (2) improving scheduling efficiency; (3) revealing massive planets that could be mistaken for Earth-mass planets; (4) providing the surface gravities necessary for interpreting atmospheric spectra and potential biosignatures.
The Next Generation of Cosmological Measurements with Type Ia Supernovae, by Daniel Scolnic, Duke University NASA ADS record: 2019astro2020T.270S/abstract The next era promises to be extremely exciting in the number of different ways SNe Ia are used to measure various cosmological parameters. Here we review the experiments in the 2020s that will yield orders of magnitudes more SNe Ia and we discuss five different cosmological probes with SNe Ia.
Exploring Beyond-the-Standard-Model Physics with TeV Gamma-rays, by J. Patrick Harding, Los Alamos National Laboratory NASA ADS record: 2019BAAS...51c.272H/abstract We consider three well-motivated beyond-the-Standard-Model searches for which the next generation of high-energy observatories will be well-suited: dark matter in the forms of primordial black holes and axion-like particles and violations of Lorentz invariance.
The Next Generation Celestial Reference Frame, by Megan Johnson, United States Naval Observatory NASA ADS record: 2019BAAS...51c.273J/abstract Astrometry is the fundamental cornerstone for all areas of Astronomy. The IAU adopted International Celestial Reference Frame (ICRF) consists of radio positions of 4536 quasars. In order to maintain and improve the accuracy of the ICRF, we require a next generation radio telescope with long baselines and high sensitivity such as the ngVLA.
Mapping the Inner Structure of Quasars with Time-Domain Spectroscopy, by Yue Shen, University of Illinois NASA ADS record: 2019BAAS...51c.274S/abstract This White Paper discusses the needs to understand the accretion processes of quasars and to measure their fundamental physical properties using time-domain spectroscopy, and opportunities from future surveys and facilities in the upcoming landscape of time-domain astrophysics.
MULTIMESSENGER UNIVERSE
with GRAVITATIONAL WAVES from BINARY SYSTEMS, by Bangalore Sathyaprakash, The Pennsylvania State University NASA ADS record: 2019BAAS...51c.276S/abstract Future GW detector networks and EM observatories will provide a unique opportunity to observe the most luminous events in the Universe involving matter in extreme environs. They will address some of the key questions in physics and astronomy: formation and evolution of compact binaries, sites of formation of heavy elements and the physics of jets.
Astrophysical magnetized turbulence and turbulent dynamo in laser-driven plasma experiments, by Petros Tzeferacos, University of Chicago NASA ADS record: 2019BAAS...51c.278T/abstract This white paper describes recent experimental breakthroughs and research opportunities in laboratory astrophysics on the topics of magnetized turbulence and turbulent dynamo. These fundamental processes are relevant to the evolution and dynamics of the interstellar and intergalactic mediums.
The Future Landscape of High-Redshift Galaxy Cluster Science, by Adam Mantz, KIPAC, Stanford University NASA ADS record: 2019BAAS...51c.279M/abstract We describe the opportunities for galaxy cluster science in the high-redshift regime where massive, virialized halos first formed and where star formation and AGN activity peaked. New observing facilities from radio to X-ray wavelengths, combining high spatial/spectral resolution with large collecting areas, are poised to uncover this population.
Imprint of Drivers of Galaxy Formation in the Circumgalactic Medium, by Benjamin Oppenheimer, University of Colorado, Boulder NASA ADS record: 2019BAAS...51c.280O/abstract A sensitive X-ray telescope can bring about a revolution in observations of the CGM. Its hot component, now mostly undetected, will be richly mapped around normal galaxies. These observations, augmented by advances in the radio and a continued progress in the UV and mm-waves, will expose the missing pieces of our understanding of galaxy formation.
Indirect Detection of Extrasolar Planets via Radio Wavelength Astrometry, by Bryan Butler, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.281B/abstract Extrasolar giant planets in nearly face-on orbits are difficult to detect with transit or radial velocity techniques. They could be detected with a radio interferometer with sufficient resolution and sensitivity, via the wobble of the central star due to the orbiting planet. The next generation Very Large Array (ngVLA) is such an instrument.
Tomography of the Cosmic Dawn and Reionization Eras with Multiple Tracers, by Tzu-Ching Chang, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.282C/abstract We advocate a multi-tracer, large-scale approach to study the reionization and cosmic dawn eras. We highlight the line intensity mapping technique to trace the multi-phase reionization topology on large scales and reionization history in detail. We also advocate for Lya tomography mapping as an additional probe besides 21cm of the cosmic dawn era.
A Direct Measure of Cosmic Acceleration, by Stephen Eikenberry, University of Florida NASA ADS record: 2019BAAS...51c.283E/abstract Two decades after the discovery of accelerating cosmic expansion, there remains no direct detection of a change in the expansion velocity versus time. Redshift drift directly determines H(z), thus it is arguably the cleanest measurement of expansion history. Dedicated experiments can detect redshift drift with a five-year observational baseline.
Ultra-heavy cosmic-ray science: Are r-process nuclei in the cosmic rays produced in supernovae or binary neutron star mergers?, by Walter Binns, Washington University in St. Louis NASA ADS record: Galactic cosmic rays play an important role in the dynamics of matter and magnetic fields in the interstellar medium, and probably also in star formation. There is an opportunity during the coming decade to answer these questions by measuring the relative abundances of every individual element heavier than iron, including the actinides.
Probing the Black Hole Engine with Measurements of the Relativistic X-ray Reflection Component, by Javier Garcia, California Institute of Technology NASA ADS record: 2019BAAS...51c.284G/abstract We discuss the observational and theoretical challenges expected in the exploration, discovery, and study of astrophysical black holes in the next decade. We focus on the case of accreting black holes and their electromagnetic signatures, with particular emphasis on the measurement of the relativistic reflection component in their X-ray spectra.
Substellar Multiplicity Throughout the Ages, by Daniella Bardalez Gagliuffi, American Museum of Natural History NASA ADS record: 2019BAAS...51c.285B/abstract In this white paper, we advocate for a comprehensive characterization of the multiplicity properties of the substellar population as a function of age to constrain their formation and evolution, particularly across the deuterium burning boundary.
Brown Dwarfs and Directly Imaged Exoplanets in Young Associations, by Jacqueline Faherty, American Museum of Natural History NASA ADS record: 2019BAAS...51c.286F/abstract In this white paper we summarize the opportunity for discovery space in the coming decade of isolated brown dwarfs with planetary masses in young stellar associations within 150 pc. We suggest that next generation telescopes need to invest in characterizing young brown dwarfs in order to fully understand the atmospheres of sibling exoplanets.
Black Holes Across Cosmic Time, by Kayhan Gultekin, University of Michigan NASA ADS record: 2019BAAS...51c.287G/abstract In the coming decade, 30-m class telescopes will allow us to make dynamical mass measurements of the largest black holes (1) in the local universe, which is critical for understanding the black hole mass function, and (2) out to z~1.5, which is critical for black hole growth and charting the coevolution (or not) of black holes and galaxies.
Radial Metallicity Gradients in Star-Forming Galaxies, by Letizia Stanghellini, National Optical Astronomy Observatory NASA ADS record: 2019BAAS...51c.288S/abstract Radial metallicity gradients of star-forming galaxies have been successfully used to set important constraints on galaxy formation and chemical evolution. This paper focuses on the implications of radial metallicity gradients measured with different probes for a variety of galaxies, and on the foreseen advances in this field in the 2020s.
Supermassive black holes at high redshifts, by Marco Ajello, Clemson University NASA ADS record: 2019BAAS...51c.289A/abstract MeV blazars are the most luminous sources in the Universe and host supermassive black holes. An MeV survey will detect >1000 of them up to z > 5. This would allow us: to probe the formation and growth of massive black holes at high z; to pinpoint the emission region location in blazars; to determine the interplay of accretion and black hole spin.
The MeV Background, by Marco Ajello, Clemson University, USA NASA ADS record: 2019BAAS...51c.290A/abstract The emission of our Universe at MeV energies is unknown. New measurements of the intensity and the angular fluctuations of the MeV background will allow us to constrain models of SNIa formation, the evolution of radio-loud and radio-quietAGN, the growth of the most massive black holes and to constrain the cross-section for dark matter interaction
Prospects for AGN Studies at Hard X-ray through MeV Energies, by Eileen Meyer, University of Maryland Baltimore County (UMBC) NASA ADS record: 2019BAAS...51c.291M/abstract This White Paper explores advances in the study of Active Galaxies (AGN) which will be enabled by new observing capabilities at MeV energies (hard X-rays to gamma-rays; 0.1−1000 MeV), with a focus on multi-wavelength synergies.
Magnetars as Astrophysical Laboratories of Extreme Quantum Electrodynamics: The Case for a Compton Telescope, by Zorawar Wadiasingh, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.292W/abstract Magnetars, the most highly magnetic of the neutron star zoo, will serve as a prime science target for new missions surveying the MeV window. This paper outlines the core questions pertaining to magnetars and quantumelectrodynamic physics that can be addressed by new technologies with spectropolarimetric capability in the 0.1-100 MeV energy range.
Mapping Galaxy Clusters in the Distant Universe, by Helmut Dannerbauer, Instituto de AstrofÃsica de Canarias, Universidad de La Laguna NASA ADS record: 2019BAAS...51c.293D/abstract We present the science case for mapping several thousand galaxy (proto)clusters at z=1-10 with a large aperture single dish sub-mm facility, producing a high-redshift counterpart to local large surveys of rich clusters like the well-studied Abell catalogue.
The Early Evolution of Stars and Exoplanet Systems: Exploring and Exploiting Nearby, Young Stars, by Joel Kastner, Rochester Institute of Technology NASA ADS record: 2019BAAS...51c.294K/abstract We describe how our understanding of a wide range of aspects of the astrophysics of young stars and planetary systems is ripe for progress over the next decade via the identification and study of nearby (D <= 120 pc), young (age < 750 Myr) stars with present and next-generation facilities and instruments.
Gravity and Light: Combining Gravitational Wave and Electromagnetic Observations in the 2020s, by Ryan Foley, UC Santa Cruz NASA ADS record: 2019BAAS...51c.295F/abstract Within ten years, we will detect hundreds of GW events. We will explore exotic astrophysical topics ranging from nucleosynthesis, stellar evolution, general relativity, high-energy astrophysics, nuclear matter, to cosmology. We outline some of the most exciting scientific questions that can be answered by combining GW and EM observations.
The Dynamic Infrared Sky, by Mansi Kasliwal, California Institute of Technology NASA ADS record: 2019BAAS...51c.296K/abstract Opening up the dynamic infrared sky for systematic time-domain exploration would yield many scientific advances in multi-messenger astrophysics, stellar evolution and high energy physics. We discuss challenges and pathfinders to overcome them. We conclude with recommendations on both infrared discovery and follow-up to flourish in the next decade.
Probing Feedback in Galaxy Formation with Millimeter-wave Observations, by Nicholas Battaglia, Cornell University NASA ADS record: 2019BAAS...51c.297B/abstract The next decade of mm-wave observations will transform our understanding of galaxy formation, driven by precisely measuring the thermodynamic properties of ionized gas, using the cosmic microwave background as a ``backlight''. Â These observations will probe gas well into the outskirts of hitherto-unexplored high-redshift, low-mass systems.
The radio search for technosignatures in the decade 2020–2030, by Jean-Luc Margot, University of California, Los Angeles NASA ADS record: 2019BAAS...51c.298M/abstract Advancing the scientific frontier in the search for life in the universe requires support of searches for both biosignatures and technosignatures. A modest budgetary increment can expand the search for life in the universe from primitive to complex life and from the solar neighborhood to the entire Galaxy.
Understanding Activity in Small Solar System Bodies, by Daniel Boice, Scientific Studies and Consulting NASA ADS record: 2019BAAS...51c.299B/abstract Gas and dust activity in small Solar System bodies is essential to understanding the clues that these objects hold concerning the conditions of the early Solar System. However, many important questions remain about the mechanisms of activity, including outbursts. We propose several research pathways to address this lack of knowledge.
EUV observations of cool dwarf stars, by Allison Youngblood, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.300Y/abstract The EUV (100-912 Ã…) probes regions of the stellar atmosphere that are inaccessible from other spectral regions, including cool coronal emission lines that offer the clearest path toward detecting coronal mass ejections on stars other than the Sun. New EUV observations would require a dedicated grazing-incidence observatory.
Far Reaching Science with Resolved Stellar Populations in the 2020s, by Benjamin Williams, University of Washington NASA ADS record: 2019BAAS...51c.301W/abstract We describe the many fields in astronomy that will benefit from resolved stellar population studies in the 2020s. We focus on the significant progress that we expect from projects currently under construction, and in this context, what will be the most impactful capabilities for which to strive in the longer term.
LSST Narrowband Filters, by Peter Yoachim, Univeristy of Washington NASA ADS record: 2019BAAS...51c.303Y/abstract We discuss the technical considerations of using narrowband filters with the LSST and lay out the scientific impact that would result on the study of AGB stars, emission line nebula (e.g., supernova remnants and planetary nebulae), photometric redshifts of galaxies, and the determination of stellar parameters.
WFIRST: Enhancing Transient Science and Multi-Messenger Astronomy, by Ryan Foley, UC Santa Cruz NASA ADS record: 2019BAAS...51c.305F/abstract Ground-based observatories will discover thousands of transients in the optical, but will not provide the NIR photometry and high-resolution imaging of a space-based observatory. WFIRST can fill this gap. With its SN Ia survey, WFIRST will also discover thousands of other transients in the NIR, revealing the physics for these high-energy events.
Kilonovae: nUV/Optical/IR Counterparts of Neutron Star Binary Mergers with TSO, by Brian Metzger, Columbia University NASA ADS record: 2019astro2020T.306M/abstract UVOIR emission from binary NS mergers informs their nucleosynthesis and the properties of NSs. TSO is a Probe-class 1.3m telescope, with imaging/spectroscopy (R = 200, 1800) in 4 bands (0.3 - 5μm) and rapid slew capability to 90% of sky. TSO nUV-mid-IR spectra of LIGO-detected mergers will provide new constraints on NS structure/nucleosynthesis.
Radio Observational Constraints on Turbulent Astrophysical Plasmas, by Tim Bastian, National Radio Astronomy Observatory NASA ADS record: 2019astro2020T.307B/abstract Using radio observations of background sources, scattering phenomena may be used to characterize the properties of foreground turbulent plasma. We discuss the potential of such techniques to explore turbulence in the solar wind and interstellar medium. The Next Generation VLA will be an ideal instrument to exploit these techniques.
Searching for TeV Dark Matter in the Milky Way Galactic Center, by Aion Viana, Instituto de FÃsica de São Carlos, Universidade de São Paulo, Brazil NASA ADS record: 2019BAAS...51c.308V/abstract We present the prospects to detect and identify dark matter particles through the observation of very-high-energy gamma rays coming from the annihilation or decay of these particles in the Galactic halo. Observations with future high-energy observatories would reach unprecedented sensitivity to dark matter particles with masses in the TeV scale.
On The Unique Value of Spectroscopy in the Deep Ultraviolet for Galaxy Evolution Studies, by Todd Tripp, University of Massachusetts - Amherst NASA ADS record: 2019BAAS...51c.309T/abstract We discuss, with real data examples, a largely unexplored discovery space for CGM studies: the diagnostic-rich deep ultraviolet at rest wavelengths < 912 A. The resonance lines of a wide array of ions are in this region, but they can be accessed by studying QSO absorbers with sufficient redshift to bring the lines into the observable UV band.
Gravitational wave cosmology and astrophysics with large spectroscopic galaxy surveys, by Antonella Palmese, Fermi National Accelerator Laboratory NASA ADS record: 2019BAAS...51c.310P/abstract During the next decade, measurements of the Hubble constant from gravitational wave standard sirens will potentially reach a 1-2% uncertainty. The next generation of spectroscopic galaxy surveys will play a crucial role towards achieving such precision, and towards improving our understanding of gravitational wave sources.
Pulsars in a Bubble? Following Electron Diffusion in the Galaxy with TeV Gamma Rays, by Henrike Fleischhack, Michigan Technological University NASA ADS record: 2019BAAS...51c.311F/abstract TeV Halos, extended regions of gamma-ray emission around pulsars, are a new class of gamma-ray sources. They can be used to study pulsar properties and e+e- diffusion on scales of ~10 pc, as well as to find misaligned pulsars. We outline the contributions of future gamma-ray instruments to the study of TeV Halos and the expected physics outcomes.
Mapping out the time-evolution of exoplanet processes, by Jessie Christiansen, Caltech/IPAC-NExScI NASA ADS record: 2019BAAS...51c.312C/abstract In this white paper we identify predicted correlations, particularly trends in exoplanet populations, radii, orbits and atmospheres with host star age, that will allow us to begin identifying the dominant processes governing the formation and evolution of exoplanet systems.
High-Dimensional Dust Mapping, by Gail Zasowski, University of Utah NASA ADS record: 2019BAAS...51c.314Z/abstract This white paper describes the impact of mapping 3D dust properties in the Milky Way, including extinction curve behavior and dynamics, and the observations needed to achieve these goals.
Local Constraints on Supermassive Black Hole Seeds, by Richard Plotkin, University of Nevada, Reno NASA ADS record: 2019BAAS...51c.315P/abstract This white paper discusses how proposed multiwavelength facilities going into the 2020s/2030s will allow us to assemble large samples of weakly accreting active galactic nuclei in low-mass galaxies, in order to constrain the mass-distribution of objects that originally seeded the growth of supermassive black holes.
Probing the Interstellar Medium in the 2020s and Beyond, by Nicolas Flagey, Canada-France-Hawaii Telescope Corporation NASA ADS record: 2019BAAS...51c.316F/abstract We describe how a dedicated facility with a wide field of view, large aperture, highly multiplexed, multi-object, high resolution spectrograph will unify our understanding of the gas structure in galaxies by placing measurements of interstellar absorption features used to trace diffuse gas on an equal footing with those of H I and CO emission.
High-Resolution X-ray Imaging Studies of Neutron Stars, Pulsar Wind Nebulae and Supernova Remnants, by Samar Safi-Harb, University of Manitoba NASA ADS record: 2019BAAS...51c.317S/abstract Supernova remnants and neutron stars serve as nearby laboratories relevant to many areas in Astrophysics. In this white paper, we highlight some science breakthroughs to be achieved with future X-ray missions (such as the proposed AXIS probe) equipped with sub-arcsecond imaging resolution and an order of magnitude improvement in sensitivity.
Detecting Offset Active Galactic Nuclei, by Laura Blecha, University of Florida, Gainesville, FL, USA NASA ADS record: 2019astro2020T.318B/abstract Gravitational wave (GW) and gravitational slingshot recoil kicks can produce active galactic "nuclei" that are offset from the centers of their host galaxies. We highlight opportunities to detect offset AGN with future telescopes and describe how these observations would provide key constraints on SMBH binaries and GW event rates.
Radio Time-Domain Signatures of Magnetar Birth, by Casey Law, UC Berkeley NASA ADS record: 2019BAAS...51c.319L/abstract We consider the implications of an emerging consensus on the origin of a diverse set of luminous astrophysical transients, such as FRBs, SLSNe, and ULGRBs. Each of these classes could be interpreted as a signature of magnetar birth. We describe how radio transients from milliseconds to gigaseconds will be used to address diverse physical questions.
EUV influences on exoplanet atmospheric stability and evolution, by Allison Youngblood, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.320Y/abstract EUV photons (100-912 Ã…) drive atmospheric mass loss, and an accurate accounting of the EUV in a planet's energy budget is essential. Direct EUV observations of exoplanet host stars would require a new, dedicated observatory. Archival observations from EUVE and models are insufficient to accurately characterize EUV spectra of exoplanet host stars.
Opportunities in Time-Domain Extragalactic Astrophysics with the NASA Near-Earth Object Camera (NEOCam), by Nicholas Ross, University of Edinburgh NASA ADS record: 2019BAAS...51c.321R/abstract This White Paper motivates the time domain extragalactic science case for the NASA Near-Earth Object Camera (NEOCam). Using the NEOWISE-R model, for relatively little cost, additional NEOCam data processing will have a massive scientific and legacy impact on extragalactic science, especially in the nascent field of AGN IR variability studies.
Toward Finding Earth 2.0: Masses and Orbits of Small Planets with Extreme Radial Velocity Precision, by David Ciardi, Caltech/IPAC-NExScI NASA ADS record: 2019BAAS...51c.322C/abstract Having discovered that Earth-sized planets are common, we are now embarking on a journey to determine if Earth-like planets are also common. To achieve this forward-looking goal, we must determine the masses and orbits of the planets; as such, the development of high quality precision radial velocity instruments and facilities is needed.
Diagnostics of Space Weather Drivers Enabled by Radio Observations, by Tim Bastian, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.323B/abstract The Sun is an active star that can impact the Earth, its magnetosphere, and the technological infrastructure on which modern society depends. Radio emission from space weather drivers offers unique diagnostics that complement those available at other wavelengths. We discuss the requirements for an instrument to enable such diagnostics.
Interplanetary dust around main sequence stars: origin, magnitude, and implications for exoplanet habitability searches, by Bertrand Mennesson, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.324M/abstract The brightness and spatial distribution of warm (≳200K) dust structures located within a few AU We motivate and identify here the main instrumental / observational advances required to gain further insights into the origins of exozodiacal dust clouds and better understand their impact on planetary habitability and habitability searches.
Probing 3D Density and Velocity Fields of ISM in Centers of Galaxies with Future X-Ray Observations, by Eugene Churazov, MPA NASA ADS record: 2019BAAS...51c.325C/abstract Presence of large quantities of molecular gas in the vicinity of Sgr A* opens the possibility for synergetic studies of the supermassive black hole's past outbursts and the fundamental properties of the molecular clouds themselves. The full potential of this synergy can only be exploited with the next generation of X-ray observatories.
Supermassive Black Hole Feedback, by Mateusz Ruszkowski, University of Michigan in Ann Arbor NASA ADS record: 2019BAAS...51c.326R/abstract Galaxy evolution is critically shaped by the energy injection from supermassive black holes (SMBHs). A major challenge is unraveling how the energy released near the SMBHs is distributed throughout galaxies and their environments. This white paper discusses the prospect of tackling this problem using high-resolution X-ray/microwave observations.
Constraining Stellar Photospheres as an Essential Step for Transmission Spectroscopy of Small Exoplanets, by Benjamin Rackham, University of Arizona NASA ADS record: 2019BAAS...51c.328R/abstract Transmission spectra probe the atmospheres of transiting exoplanets, but these observations are also subject to signals introduced by magnetic active regions on host stars. We outline scientific opportunities in the next decade for providing useful constraints on stellar photospheres for the purposes of exoplanet transmission spectroscopy.
Tracking the Baryon Cycle in Emission and in Absorption, by Hsiao-Wen Chen, The University of Chicago NASA ADS record: 2019BAAS...51c.329C/abstract This white paper describes the power of combining emission detections from wide-area integral field spectroscopy and absorption observations from echelle spectroscopy to enable the construction of spatially and spectrally resolved maps of gas flows in and out of galaxies and supermassive black holes across cosmic time.
Tracking the time-variable Millimeter-wavesky with CMB experiments, by Gilbert Holder, University of Illinois at Urbana-Champaign NASA ADS record: 2019BAAS...51c.331H/abstract Cosmic microwave background experiments make wide-area, sensitive, high-cadence maps of the sky at mm-wavelengths. Discoveries will include moving (solar system objects), time-variable (stars, active galactic nuclei), or transient sources (novae, tidal disruption events, gamma-ray bursts, nearby supernovae, gravitational wave events) .
Precision Analysis of Evolved Stars, by Stephen Ridgway, NOAO NASA ADS record: 2019BAAS...51c.332R/abstract The broad recommendation of this paper is three-fold: recognize the essential role of stellar physics in all of astronomy and cosmology; note that a revolution in stellar measurement capabilities, datasets, and modeling is underway and gaining momentum; and support the scientists, their essential technologies and observatories.
Low Mass Stars as Tracers of Star Formation in Diverse Environments, by Tom Megeath, University of Toledo NASA ADS record: 2019BAAS...51c.333M/abstract Young low mass stars and protostars are tracers of star formation across the diverse natal environments found in our galaxy. Here we describe how surveys for young low mass stars and protostars can probe how environment influences the star formation rate, the IMF and the formation of bound clusters.
Science Platforms for Resolved Stellar Populations in the Next Decade, by Knut Olsen, National Optical Astronomy Observatory NASA ADS record: 2019BAAS...51c.334O/abstract Large surveys of resolved stellar populations in the next decade will explore the nature of dark matter, unravel the star formation, chemical enrichment, and dynamical histories of the Milky Way and nearby galaxies, and probe fundamental physics. Data archives and Science Platforms will be critical to bringing their discoveries to fruition.
On the Origins of the Initial Mass Function, by Roberta Paladini, Caltech-IPAC NASA ADS record: 2019BAAS...51c.335P/abstract In order to establish if the IMF and CMF are Universal, it is necessary to: 1) perform multi-wavelength large-scale imaging and spectroscopic surveys; 2) require an angular resolution of <0:1" in the optical/near-IR and <5"in the far-IR; 3) achieve far-IR sensitivities to probe 0.1 M cores at 2–3 kpc.
Supermassive Black-hole Demographics &Environments With Pulsar Timing Arrays, by Stephen Taylor, California Institute of Technology NASA ADS record: 2019BAAS...51c.336T/abstract Precision timing of large arrays (>50) of millisecond pulsars will detect the nanohertz gravitational-wave emission from supermassive binary black holes within the next ~3−7 years. We review the scientific opportunities of these detections, the requirements for success, and the synergies with electromagnetic instruments operating in the 2020s.
Discovery Frontiers of Explosive Transients: An ELT and LSST Perspective, by Melissa Graham, University of Washington NASA ADS record: 2019BAAS...51c.339G/abstract We present several examples of future scientific impacts in the field of explosive transient astrophysics that will be generated by the combination of discoveries with the Large Synoptic Survey Telescope and follow-up with the Extremely Large Telescopes, and discuss practical aspects such as data infrastructures required to enable LSST+ELT synergy.
Triggered High-Priority Observations of Dynamic Solar System Phenomena, by Nancy Chanover, New Mexico State University NASA ADS record: 2019BAAS...51c.340C/abstract Observations of unexpected dynamic phenomena will lead to important discoveries about solar system workings. We advocate for long-term/permanent programs on ground-based and space-based telescopes of all sizes -- including Extremely Large Telescopes (ELTs) -- to conduct observations of high-priority dynamic solar system phenomena.
WFIRST: The Essential Cosmology Space Observatory for the Coming Decade, by Olivier Dore, JPL/Caltech NASA ADS record: 2019BAAS...51c.341D/abstract Two decades after its discovery, cosmic acceleration remains the most profound mystery in cosmology. WFIRST emerged as a top priority of Astro2010 in part because of its ability to address the mystery of cosmic acceleration in powerful ways. Mission design changes since Astro2010 have made WFIRST an even more powerful dark energy facility.
Debris Disk Composition: A Diagnostic Tool for Planet Formation and Migration, by Christine Chen, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.342C/abstract Detailed studies of debris disk composition studies can address the scientific questions: (1) Are debris disk minor bodies similar to asteroids and comets in our Solar System? (2) Do planets separate circumstellar material into distinct reservoirs and/or mix material during planet migration?
Technosignatures in Transit, by Jason Wright, Penn State University NASA ADS record: 2019BAAS...51c.343W/abstract TESS, and similar time-domain photometric projects are well-suited for searches for large artificial structures orbiting other stars in the Galaxy. An effort to identify anomalous transit events in these photometry datasets, and a robust follow-up program to understand them, would enable the first robust upper limits on such megastructures.
Transverse Extragalactic Motions: a New Method for Constraining Cosmological Parameters, by Michael Pierce, University of Wyoming NASA ADS record: 2019BAAS...51c.344P/abstract The geometrical nature of strong lensing can provide cosmological constraints that are independent of the traditional methods. Specifically, multiple-arc systems where a single lens images multiple background objects and via a new method based on cosmological parallax from the Galaxy's motion with respect to the Cosmic Microwave Background.
Protoplanetary Disk Science Enabled by Extremely Large Telescopes, by Hannah Jang-Condell, University of Wyoming NASA ADS record: 2019BAAS...51c.346J/abstract We discuss how a spectroscopic and imaging survey of protoplanetary disks with Extremely Large Telescopes will enhance our understanding of planet formation by (1) measuring the physical and chemical conditions in disks using infrared spectroscopy and (2) studying planet-disk interactions using imaging and spectro-astrometry.
The Multidimensional Milky Way, by Robyn Sanderson, University of Pennsylvania / Flatiron Institute NASA ADS record: 2019BAAS...51c.347S/abstract In the next decade our understanding of the Milky Way's dynamics, stellar populations, and structure will be revolutionized, thanks to proposed astrometric, spectroscopic and photometric surveys. We describe the new science this multidimensional view will enable across astrophysics, from constraints on dark matter to insights into galaxy formation.
High-Energy Polarimetry - a new window to probe extreme physics in AGN jets, by Bindu Rani, NASA Goddard Space Flight Center, USA NASA ADS record: 2019BAAS...51c.348R/abstract We discuss the scientific potentials of gamma-ray polarimetry including the theoretical implications, and observational technology advances being made. We explore the primary scientific opportunities and wealth of information expected from synergy of multi-wavelength polarimetry that will be brought to multi-messenger astronomy.
Are Supernovae the Dust Producer in the Early Universe?, by Jeonghee Rho, SETI Institute NASA ADS record: 2019BAAS...51c.351R/abstract The large quantities of dust in high-redshift galaxies raise a fundamental question as to the origin of dust in the early Universe. Supernovae occur within several millions of years. This white paper will focus on dust formation in SN ejecta with US-Extremely Large Telescope (ELT) perspective during the era of JWST and LSST.
Venus as a Nearby Exoplanetary Laboratory, by Stephen Kane, University of California, Riverside NASA ADS record: 2019BAAS...51c.353K/abstract Venus provides a unique opportunity to explore the processes that create hostile environments and define the boundaries of habitability. We advocate a continued comprehensive study of our sister planet, including models of early atmospheres, compositional abundances, and Venus-analog frequency analysis from current and future exoplanet data.
THE VALUE OF ASTROMETRY FOR EXOPLANET SCIENCE, by Eduardo Bendek, NASA Ames Research Center NASA ADS record: 2019BAAS...51c.354B/abstract We describe the scientific importance of measuring exoplanet masses and how high-precision astrometry can be utilized for this purpose. We describe current technology development efforts and astrometry missions concepts being proposed by the community to detect and characterize exoplanets.
The Next Decade of Astroinformatics and Astrostatistics, by Aneta Siemiginowska, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c.355S/abstract Over the past century, major advances in astronomy and astrophysics have been driven by improvements in instrumentation. With the amassing of high quality data from new telescopes it is becoming clear that research in astrostatistics and astroinformatics will be necessary to develop new methodology needed in astronomy.
Characterizing Exoplanet Habitability, by Tyler Robinson, Northern Arizona University NASA ADS record: 2019BAAS...51c.356R/abstract Characterizing habitable exoplanets is a critical, aspirational goal for astronomy and astrophysics. We discuss a range of habitability indicators and their associated observing requirements. These requirements highlight next generation space telescopes as the key to studying habitable environments outside the Solar System.
All-Sky time domain astrophysics with Very High Energy Gamma rays, by Fabian Schussler, IRFU, CEA Paris-Saclay NASA ADS record: 2019BAAS...51c.357S/abstract Transient astronomy has witnessed a remarkable evolution with recent discoveries across all astrophysical messengers. We here discuss present key examples of transient sources which would be prime targets for wide field-of-view ground-based observatories observing in the very-high-energy gamma-ray domain.
Deep Multi-object Spectroscopy to Enhance Dark Energy Science from LSST, by Jeffrey Newman, University of Pittsburgh and PITT PACC NASA ADS record: 2019BAAS...51c.358N/abstract This white paper describes the science opportunities to greatly improve measurements of cosmological parameters from LSST which would be made possible by community access to deep (i~25), highly-multiplexed OIR multi-object spectroscopy (MOS) on 8--40m telescopes. Companion papers discuss opportunities from wide-field MOS and single-object data.
Unveiling Cosmic Dawn: the synergetic role of space and ground-based telescopes, by Jean-Gabriel Cuby, University of Aix-Marseille NASA ADS record: 2019BAAS...51c.360C/abstract Euclid and WFIRST will find thousands of galaxies and quasars above redshift 7 during the epoch of reionization. Massive spectroscopic follow-up campaigns with existing and planned near-infrared and mm facilities will be required for confirmation and physical characterization. A properly coordinated large follow-up campaign is recommended.
Extreme Plasma Astrophysics, by Dmitri Uzdensky, University of Colorado Boulder NASA ADS record: 2019BAAS...51c.362U/abstract This white paper describes the present status and emerging opportunities in Extreme Plasma Astrophysics -- a study of astrophysically-relevant plasma processes taking place under extreme conditions that necessitate taking into account relativistic , radiation, and QED effects.
Wide-field Multi-object Spectroscopy to Enhance Dark Energy Science from LSST, by Rachel Mandelbaum, Carnegie Mellon University NASA ADS record: 2019BAAS...51c.363M/abstract This white paper describes the opportunities to greatly improve measurements of cosmological parameters from LSST made possible by community access to wide-field (>20 sq. deg. total area), highly-multiplexed OIR multi-object spectroscopy (MOS) on 4-15m telescopes. Companion papers discuss opportunities from deeper MOS and single-object data.
Solar System's minor bodies: the role of the ngVLA, by Arielle Moullet, USRA/SOFIA NASA ADS record: 2019BAAS...51c.364M/abstract Thermal observations of minor bodies in the Solar System , and in particular centimeter-wave measurements probing across the diurnal skin depth, are strongly indicative of fundamental properties of their surfaces. We describe how the sensitivity provided by the ngVLA is necessary to achieve thermal detections on a large number of small bodies.
From Stars to Compact Objects: The Initial-Final Mass Relation, by Jessica Lu, UC Berkeley NASA ADS record: 2019BAAS...51c.365L/abstract We lack a predictive model for how a star of a given mass explodes and what kind of remnant it leaves behind (i.e. the initial-final mass relation, IFMR). Astrometric gravitational lensing offers a new way to find and weigh compact objects and place the first constraints on the IFMR, compact object multiplicity, and kick velocities.
Technosignatures in the Thermal Infrared, by Jason Wright, Penn State University NASA ADS record: 2019BAAS...51c.366W/abstract WISE and Gaia ​ provide an opportunity for the first robust upper limits on the energy supplies of extraterrestrial civilizations, both for stars in the Galaxy and for other galaxies. JWST​ will provide the MIR spectroscopy necessary to identify the origin of infrared excesses, advancing both traditional astronomy and searches for technosignatures.
The Cycling of Matter from the Interstellar Medium to Stars and back, by Robert Simon, Universitaet zu Koeln NASA ADS record: 2019BAAS...51c.367S/abstract Many open questions regarding cloud and structure formation, the role of turbulence, and the relative importance of different feedback processes in the interstellar medium can only be addressed with observations of spectrally resolved lines. We here stress the importance of wide field surveys in atomic carbon and mid-J CO lines.
Understanding the circumgalactic medium is critical for understanding galaxy evolution, by Molly Peeples, Space Telescope Science Institute / Johns Hopkins University NASA ADS record: 2019BAAS...51c.368P/abstract The circumgalactic medium is a major reservoir of baryons and metals, playing a key role in the long cycles of accretion, feedback, and recycling of gas driving galaxy evolution. Fundamental progress on major issues in galaxy evolution depends critically on improved empirical characterization and theoretical understanding of circumgalactic gas.
Single-object Imaging and Spectroscopy to Enhance Dark Energy Science from LSST, by Renée Hložek, Department of Astronomy and Astrophysics & Dunlap Institute for Astronomy and Astrophysics, University of Toronto NASA ADS record: 2019BAAS...51c.369H/abstract This white paper describes the science opportunities to greatly improve measurements of cosmological parameters from LSST made possible by community access to single-object imaging and spectroscopy on telescopes with apertures ranging from 4-40m. Companion papers discuss opportunities from both deep and wide-field multi-object spectroscopy.
Variability in the Assembly of Protostellar Systems, by Joel Green, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.372G/abstract The impact of variability on protostellar systems due to accretion bursts is largely unknown. High (spectral resolution capabilities with rapid response times in the IR, X-ray, and radio are critical to follow the course of accretion and outflow during a protostellar outburst. This is not covered by currently existing or approved instrumentation.
Physical Conditions in the Cold Gas of Local Galaxies, by Adam Leroy, Ohio State University NASA ADS record: 2019BAAS...51c.373L/abstract We describe a next major frontier in studies of galaxy evolution and star formation: linking physical conditions in the cold, star-forming interstellar medium to host galaxy and local environment. The key observations will be cm-, mm-, and submm-wave spectroscopy and spectroscopic imaging. We highlight key paths for progress in the next decade.
The fundamentals of outflows from evolved stars, by Elvire De Beck, Department of Space, Earth and Environment, Chalmers University of Technology NASA ADS record: 2019BAAS...51c.374D/abstract Chemical evolution of the ISM and galaxies depends critically on stellar mass loss. We describe current efforts and future needs and opportunities to characterize AGB outflows: driving mechanisms, outflow rates, underlying fundamental physical and chemical processes such as dust grain formation, and dependency of these on metallicity.
Galactic and Extragalactic Astrochemisry: Heavy-Molecule Precursors to Life?, by carl heiles, university of california at berkeley NASA ADS record: 2019BAAS...51c.376H/abstract Dense interstellar clouds contain an astonishingly rich collection of exotic molecules in various states of ionization and excitation, revealing complex astrochemistry. Charged molecules may moderate the magnetic field during star formation. The largest ones, which may be precursors to life, are best identified at 0.5-10 GHz with big telescopes.
Thinking Big: How Large Aperture Space Telescopes Can Aid the Search for Life in Our Lifetimes, by Casey Dreier, The Planetary Society NASA ADS record: 2019BAAS...51c.377D/abstract We discuss the capabilities needed to conduct the most scientifically compelling endeavor currently facing space science: the successful search for life elsewhere. We provide the context for NASA's search for life beyond the Earth, report our assessment of public support for this science, and ways for the Astro2020 process to address this goal.
Unleashing the Potential of Dust Emission as a Window onto Galaxy Evolution, by Christopher Clark, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.378C/abstract We present the severe, systematic uncertainties currently facing our understanding of dust emission, which stymie our ability to truly exploit dust as a tool for studying galaxy evolution. We propose a program of study to tackle these uncertainties, describe the necessary facilities, and discuss the potential science gains that would result.
Prospects for Pulsar Studies at MeV Energies, by Alice Harding, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.379H/abstract Enabled by the Fermi Large Area Telescope, we now know that pulsars fill the gamma-ray sky, and we are beginning to understand their emission mechanism and their distribution throughout the Galaxy. To address key questions calls for a sensitive, wide-field MeV telescope, which can detect the population of MeV-peaked pulsars hinted at by Fermi.
The Baryon Cycle, Resolved: A New Discovery Space for UV Spectroscopy, by Jason Tumlinson, STScI / JHU NASA ADS record: 2019BAAS...51c.380T/abstract Galactic feedback arises from stars, supernovae, black holes, and radiation in a complex interplay that begins at < 100 pc scales. Future advancements in spatially resolved spectroscopy in the UV will provide unprecedented physical resolution in unique and powerful diagnostic features that are not available at other wavelengths.
The Scientific Context of WFIRST, Microlensing in the 2020s, by Jennifer Yee, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c.384Y/abstract Rather than providing a broad perspective on the WFIRST microlensing science case, this white paper explores in detail a few specific, well-defined, science questions motivated by recent research that can be answered by the WFIRST microlensing survey.
High-Energy Astrophysics in the 2020s and Beyond, by Christopher Reynolds, University of Cambridge NASA ADS record: 2019BAAS...51c.385R/abstract This White Paper illustrates the central role of high-energy astrophysics to some of the most pressing astrophysical problems of our time, the formation/evolution of galaxies, the origin of the heavy elements, star and planet formation, the emergence of life on exoplanets, and the search for new physics.
The Physics of Accretion Onto Highly Magnetized Neutron Stars, by Michael Wolff, Space Science Division, Naval Research Laboratory NASA ADS record: 2019BAAS...51c.386W/abstract Studying physical processes occurring above the magnetic poles of strongly magnetized, accreting neutron stars provides us with a laboratory for studying high temperature plasmas exposed to extreme conditions. This white paper discusses the current theoretical and observational challenges, and the importance of addressing these challenges.
Cosmic-ray Antinuclei as Messengers for Dark Matter, by Kerstin Perez, Massachusetts Institute of Technology NASA ADS record: 2019BAAS...51c.387P/abstract Low-energy antideuterons provide a “smoking gun†signature of dark matter annihilation or decay, essentially free of astrophysical background. Low-energy antiprotons are a vital partner for this analysis, and low-energy antihelium could provide further discovery space for new physics.
Characterizing the Assembly of Galaxy Cluster Populations Over Cosmic time, by Michael Pierce, University of Wyoming NASA ADS record: 2019BAAS...51c.388P/abstract The coming ELTs promise to revolutionize our understanding of the assembly and evolution of galaxies near the epoch of peak assembly (z ~ 2). However, complementary data sets for lower redshift populations will be be necessary to fully complement the ELT surveys. An extensive, survey of the elliptical populations in 1 < z clusters is advocated.
Searches for Technosignatures in Astronomy and Astrophysics, by Jason Wright, Penn State University NASA ADS record: 2019BAAS...51c.389W/abstract Recent advances in observation, instrumentation, and our understanding of exoplanets make the search for technosignatures (i.e. SETI) is a compelling scientific theme for the coming decade. This white paper introduces the subject, highlights results from the NASA Technosignatures workshop, and identifies key advances necessary in the next decade.
Magnetic Fields and Polarization in the Diffuse Interstellar Medium, by Susan Clark, Institute for Advanced Study NASA ADS record: 2019BAAS...51c.390C/abstract Magnetism is one of the most important forces on interstellar gas dynamics, star formation, and Galactic evolution. The next decade will transform our understanding of interstellar magnetism if we invest in polarimetry: surveys of polarized dust emission, starlight polarization, and single-dish measurements of Zeeman splitting.
Exocometary Science, by Luca Matra, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c.391M/abstract This paper describes recent advances that led to the emergence of Exocometary Science, with an outlook and recommendations for the field to prospect in future decades. These studies provide a window into the composition and dynamics of exocomets, extrasolar icy minor bodies, as observed at the epoch of volatile delivery to inner rocky planets.
Molecular Masers as Probes of the Dynamic Atmospheres of Dying Stars, by Lynn D. Matthews, Massachusetts Institute of Technology Haystack Observatory NASA ADS record: 2019BAAS...51c.392M/abstract The atmospheres of mass-losing red giants are characterized by the interplay between complex and dynamic processes. In the coming decade, observations of the molecular masers in the outflows of evolved stars with ultra-high angular resolution using VLBI are poised to provide groundbreaking insights into the physics of late-stage stellar mass-loss.
Mapping Cosmic Dawn and Reionization: Challenges and Synergies, by Paul La Plante, University of Pennsylvania NASA ADS record: 2019BAAS...51c.394L/abstract Cosmic dawn and the Epoch of Reionization are among the least explored observational eras in cosmology. To maximize scientific discovery and return on investment, coordinated survey planning and joint data analysis from experiments probing this epoch should be a high priority, closely coupled to the computational models and theoretical predictions.
Assembly of the Most Massive Clusters at Cosmic Noon, by Jeyhan Kartaltepe, Rochester Institute of Technology NASA ADS record: 2019BAAS...51c.395K/abstract The next decade will see a transformational shift in our understanding of protoclusters as deep spectroscopy over wide fields of view will be possible in conjunction with high resolution deep imaging in the optical and near-infrared, enabling the characterization of their overall structure, the galaxies within them, and the gas that feeds them.
High Definition Astrometry, by Philip Horzempa, LeMoyne College NASA ADS record: Description of the Science Case for a Probe-class high-precision astrometry mission for exoplanet exploration
Energetic Particles of Cosmic Accelerators I: Galactic Accelerators, by Tonia Venters, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.396V/abstract This white paper is the first of a two-part series highlighting the most well-known high-energy cosmic accelerators and contributions that MeV astronomy will bring to understanding their energetic particle phenomena. The paper discusses galactic cosmic rays, supernova remnants, protostellar jets and superbubbles, and colliding wind binaries.
Interstellar Dust Grains: Ultraviolet and Mid-IR Extinction Curves, by Karl Gordon, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.397G/abstract Interstellar dust extinction curves in the UV and MIR to probe the 2175 A bump (carbonaceous), 3.4 micron (carbonaceous), and 10/20 micron features (silicates) as one of the main pillars of our understand of dust grains. Need capabilities to obtain large samples of UV and NIR spectra of ISM sightlines throughout the Local Group.
Gamma-Ray Science in the 2020s, by Sylvain Guiriec, George Washington University / NASA Goddard Space Flight Center NASA ADS record: 2019astro2020T.398G/abstract With very large fields of view, high-cadence sampling, high angular, and spectral resolutions, and polarization capabilities, the new generation gamma-ray instruments are ready to address the most pressing science questions of the next decades, and they are essential for the time-domain multi-messenger era.
JWST: Probing the Epoch of Reionization with a Wide Field Time-Domain Survey, by Lifan Wang, Texas A&M University NASA ADS record: 2019BAAS...51c.399W/abstract A public deep and wide science enabling survey will be needed to discover these black holes and supernovae, and to cover the area large enough for cosmic infrared background to be reliably studied. This enabling survey will find a large number of other transients and enable supernova cosmology up to z $\sim$ 5.
The Chemical Enrichment History of the Universe, by J.D. Smith, University of Toledo NASA ADS record: 2019BAAS...51c.400S/abstract We describe the strong role metal abundance plays in galaxy evolution, highlight the need for absolute abundances in modern galaxy formation models, describe current obstacles clouding the cosmic chemical enrichment history, and provide a suite of new and existing methods which can track absolute metal abundance in galaxies across time.
The fastest components in stellar jets, by Hans M. Günther, MIT NASA ADS record: 2019BAAS...51c.401G/abstract Outflows and jets are a crucial component of the star formation process. The innermost components of those jets are launched close to the star and thus probe the connection between star, disk, and magnetic field. Observations with high spatial resolution in the UV and X-rays are required to probe these fast winds.
Exploration and characterization of the earliest epoch of galaxy formation: beyond the re-ionization era, by Kotaro Kohno, The University of Tokyo NASA ADS record: 2019astro2020T.402K/abstract Recent ALMA detection of the bright [OIII] 88 um line at z = 9.11, indicates the onset of star formation at z~15. In order to uncover a large number of z=10-15 galaxies, we argue two possible pathways: (1) a blind spectroscopic survey of [OIII] 88 um line emitters, and (2) a high-cadence survey of transient sources to catch the pop-III GRBs.
Mapping the CGM in Emission, by Sarah Tuttle, University of Washington, Seattle NASA ADS record: 2019astro2020T.403T/abstract Mapping the circumgalactic medium (CGM) in emission is a crucial next step to understand both the baryonic distribution of the universe and the multi-scale multi-phase medium that is a primary mediator of galaxy formation and evolution. Here we discuss the current state of the field and next steps.
Circumgalactic Gas and the Precipitation Limit, by Mark Voit, Michigan State University NASA ADS record: 2019BAAS...51c.405V/abstract Observations increasingly suggest that the ambient CGM pressure cannot exceed the limit at which cold clouds start to condense and fuel feedback that limits further condensation. Such a feedback loop tends to suspend the CGM at the threshold pressure for precipitation. The coming decade will offer many opportunities to test this principle .
Making the Connection between Feedback and Spatially Resolved Emission Line Diagnostics, by Eric Pellegrini, University of Heidelberg NASA ADS record: 2019BAAS...51c.406P/abstract We argue that crucial progress in the coming decade will depend on the ability to obtain spatially resolved spectroscopic observations of HII regions for reliable instantaneous measurements of their physical conditions, with full galactic coverage to obtain a population sample with line sensitivities significantly deeper than past efforts.
Understanding Exoplanet Atmospheres with UV Observations I: NUV and Blue/Optical, by Jessie Christiansen, Caltech/IPAC-NExScI NASA ADS record: 2019BAAS...51c.408C/abstract In this white paper we focus on the science case for exoplanet observations at near-UV/blue optical wavelengths. Scattering information encoded in at these wavelengths can distinguish the cause of muted spectral features. These wavelengths also capture atmospheric escape processes, and help characterize mass loss from exoplanet atmospheres.
Dynamical Masses for a Complete Census of Local Dwarf Galaxies, by Joshua Simon, Carnegie Observatories NASA ADS record: 2019BAAS...51c.409S/abstract The 2020s are poised to continue the past 15 years of significant advances based on the discovery and follow-up of nearby dwarf galaxies. Maximizing the scientific impact of dwarfs discovered in upcoming imaging surveys will require both major spectroscopic surveys on 6-10m telescopes and multiplexed spectroscopy with even larger apertures.
Near-Earth Supernova Explosions: Evidence, Implications, and Opportunities, by Brian Fields, University of Illinois NASA ADS record: 2019BAAS...51c.410F/abstract Geological and lunar evidence of radioactive 60Fe implies that at least one supernova exploded within 100 pc of Earth within the last few Myr. The unique information provided by 60Fe to assess nearby supernovae make now a compelling time for the astronomy community to advocate for supporting multi-disciplinary, cross-cutting research programs.
The Most Powerful Lenses in the Universe: Quasar Microlensing as a Probe of the Lensing Galaxy, by David Pooley, Trinity University NASA ADS record: 2019BAAS...51c.411P/abstract We describe how quasar microlensing is the only way to determine the dark/stellar ratio at the interesting sub-galactic scales of several kpc and how it is the only way to measure the stellar M/L outside the solar neighborhood. Both can be done as a function of redshift, and this requires sub-arcsecond X-ray imaging of LSST-discovered lenses.
The WFIRST Deep Grism Survey: WDGS, by Russell Ryan, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.413R/abstract We present several science questions that require a deep grism program with the Wide-Field Infrared Survey Telescope.
A Balancing Act: Biosignature and Anti-Biosignature Studies in the Next Decade and Beyond, by Chester Harman, Columbia University NASA ADS record: 2019BAAS...51c.414H/abstract This white paper elaborates on the need for a quantitative biosignature identification and assessment framework to produce a numerical estimate for the likelihood that a given world has life. This will provide a comprehensive means to weigh planetary habitability alongside potential biosignatures and their respective false positives.
The Panchromatic Circumgalactic Medium, by Q. Daniel Wang, University of Massachusetts Amherst NASA ADS record: 2019BAAS...51c.415W/abstract The circumgalactic medium (CGM) is empirically multi-phased and complex in dynamics. We review progress and open questions specific for the hot component, magnetic fields and cosmic rays, the cool, warm, and dusty components, and conclude with open questions primarily regarding the interplay among different components.
Advancing Understanding of Star-Planet Ecosystems in the Next Decade: The Radio Wavelength Perspective, by Rachel Osten, Space Telescope Science Institute, Johns Hopkins University NASA ADS record: In this white paper we advocate for stellar radio observations as a way to advance understanding of stars in service of a better understanding of star-planet ecosystems. Specific key advances needed are sensitivity and access to a broader range of frequency space to make progress in understanding the space weather environments of exoplanets.
The Radio Universe at Low Surface Brightness: Feedback & accretion in the circumgalactic medium, by Bjorn Emonts, National Radio Astronomy Observatory NASA ADS record: 2019astro2020T.417E/abstract The low-surface-brightness radio regime offers two novel science cases that will help understand the role of the high-z CGM in galaxy evolution: observing the cold molecular medium on scales of galaxy halos and tracing feedback through the Sunyaev-Zeldovich Effect onto the hot CGM. Compact mm interferometers will explore these new science fields.
Partnering space and ground observatories - Synergies in cosmology from LSST and WFIRST, by Tim Eifler, University of Arizona NASA ADS record: 2019BAAS...51c.418E/abstract We recommend the exploration of joint survey strategies that combine the two top-ranked survey endeavors of the 2010 Decadal Survey, the ground-based Large Synoptic Survey Telescope (LSST) and the space-based Wide Field Infrared Survey Telescope (WFIRST). We detail several joint survey scenarios and quantify the information gain for cosmology.
Probing Unseen Planet Populations with Resolved Debris Disk Structures, by Kate Su, Steward Observatory, University of Arizona NASA ADS record: 2019BAAS...51c.419S/abstract This white paper focuses on resolving debris structures in thermal emission that is applicable to a large unbiased sample. We summarize the properties of the known debris disks and assess the feasibility of resolving them within our current and future infrared and millimeter facilities by adopting uniform criteria.
Fast Radio Burst Tomography of the Unseen Universe, by Vikram Ravi, Center for Astrophysics | Harvard & Smithsonian; Caltech NASA ADS record: 2019BAAS...51c.420R/abstract The discovery of Fast Radio Bursts (FRBs) at cosmological distances has opened a powerful window on otherwise unseen matter in the Universe. Observations of >10^4 FRBs will assess the baryon contents and physical conditions in the hot/diffuse circumgalactic, intracluster, and intergalactic medium, and test extant compact-object dark matter models.
Characterizing the Atmospheres of Irradiated Exoplanets at High Spectral Resolution, by Diana Dragomir, MIT NASA ADS record: 2019BAAS...51c.422D/abstract We describe the potential of high-resolution cross-correlation spectroscopy on the Extremely Large Telescopes to 1) robustly measure atmospheric circulation and planetary rotation for hot Jupiters, and 2) measure atmospheric mass-loss and extract atmospheric composition information for sub-Neptunes, super-Earths and disintegrating planets.
Galaxy Kinematics and the Future of Dark Energy, by Eric Huff, Jet Propulsion Laboratory NASA ADS record: 2019BAAS...51c.423H/abstract We describe how galaxy kinematics can be used to greatly reduce statistical and systematic errors in weak lensing. We point out the ways in which these gains could allow kinematic lensing surveys to go beyond the limits on what is achievable with current methods, and we advocate for support for studies and instrumentation to advance the method.
Unlocking the Secrets of Late-Stage Stellar Evolution and Mass Loss through Radio Wavelength Imaging, by Lynn D. Matthews, Massachusetts Institute of Technology Haystack Observatory NASA ADS record: 2019BAAS...51c.424M/abstract Many details concerning the physics of late-stage stellar mass loss remain poorly understood. Observations at cm, mm, and sub-mm wavelengths that resolve the radio surfaces and extended atmospheres of evolved stars in space, time, and frequency are poised to provide groundbreaking new insights into these questions in the coming decade.
Solar Coronal Magnetic Fields: Quantitative Measurements at Radio Wavelengths, by Gregory Fleishman, New Jersey Institute of Technology NASA ADS record: 2019BAAS...51c.426F/abstract Quantitative measurements of coronal and chromospheric magnetic field is currently in its infancy. We describe a foundation of such observations , which is a key input for MHD numerical models of the solar atmosphere and eruptive processes, and a key link between lower layers of the solar atmosphere and the heliosphere.
Gravitationally Lensed MeV Gamma-ray Blazars, by Stefano Ciprini, INFN Rome Tor Vergata and ASI Space Science Data Center ASI, Rome, Italy NASA ADS record: 2019astro2020T.427C/abstract Gravitationally lensed gamma-ray blazars have large redshifts, huge BHs, powerful MeV photon-energy radiation. The pivotal MeV Universe is readyu for exploitation: lensed MeV blazars are rich multifreq./multimessenger laboratories (jet/central-engine spatial resolution, gamma rays/cosmic neutrinos/massive axions fluence enhancement and interference
OBSERVATIONAL ASTROCHEMISTRY IN THE NEXT DECADE, by Anthony Remijan, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.428R/abstract In order to continue to make progress in how the chemical and physical nature of molecular material changes as we move from the diffuse interstellar medium to compact cores and eventually disks with planetary systems, as a community, we need observations of large astronomical molecules over large spatial scales and bandwidths.
Cosmic evolution of supermassive black holes: A view into the next two decades, by Francesca Civano, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c.429C/abstract Discoveries over the past 20 years by Chandra and XMM-Newton surveys have significantly enhanced our view of supermassive black hole (SMBH) and galaxy evolution. We discuss new and exciting questions on the cosmic growth of SMBHs that can be addressed by new X-ray and multiwavelength observatories in the next two decades.
Unsolved Problems in Modern Astrophysics: Anomalous Microwave Emission, by Eric Murphy, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.430M/abstract This white paper discusses potential ways to improve our understanding of anomalous microwave emission (AME), requiring new facilities. AME has remained a major foreground contaminant in CMB studies since first being discovered over 20 years ago, yet its physical origin remains an unsolved problem in modern astrophysics.
Neutrinos, Cosmic Rays, and the MeV Band, by Roopesh Ojha, UMBC/NASA GSFC NASA ADS record: 2019BAAS...51c.431O/abstract The Mev band holds the key to answering three astrophysical questions: the sites where cosmic Rays are produced and accelerated, the origins of high-energy neutrinos, and the physical mechanisms producing the high energy gamma-ray emission from blazars. Theoretical and experimental capabilities needed in the next decade are discussed.
Understanding Galactic Star Formation with Next Generation X-ray Spectroscopy and Imaging, by Scott Wolk, Smithsonian Astrophysical Observatory NASA ADS record: 2019BAAS...51c.433W/abstract To address problems in the field of star formation adequately, astronomers in the 2030's will require a new X-ray telescope with arc-second imaging and of order 10,000 cm^2 collecting area. This will enable us a community to keep up with the advances which will be enabled by facilities already in development for the 2020s.
Advancing Understanding of Star-Planet Ecosystems in the Next Decade: The Radio Wavelength Perspective, by Rachel Osten, Space Telescope Science Institute, Johns Hopkins University NASA ADS record: 2019BAAS...51c.434O/abstract In this white paper we advocate for stellar radio observations as a way to advance understanding of stars in service of a better understanding of star-planet ecosystems. Specific key advances needed are sensitivity and access to a broader range of frequency space to make progress in understanding the space weather environments of exoplanets.
Stellar Characterization Necessary to Define Holistic Planetary Habitability, by Natalie Hinkel, Southwest Research Institute NASA ADS record: 2019BAAS...51c.435H/abstract It is a truism that “to know the planet, you must know the star.†We discuss important stellar characteristics that require attention in upcoming ground- and space-based missions, such that their processes can be either detangled from that of the planet, correlated with the presence of a planet, or utilized in lieu of direct planetary observations.
Cyberinfrastructure Requirements to Enhance Multi-messenger Astrophysics, by Philip Chang, University of Wisconsin - Milwaukee NASA ADS record: 2019BAAS...51c.436C/abstract We outline the cyberinfrastructure requirements to enhance multi-messenger astrophysics and argue for a distributed cyberinfrastructure institute for multimessenger astrophysics to meet these challenges and take advantages of the associate opportunities.
Physics Beyond the Standard Model With Pulsar Timing Arrays, by Xavier Siemens, University of Wisconsin -- Milwaukee NASA ADS record: 2019BAAS...51c.437S/abstract Pulsar timing arrays provide a rare opportunity to probe exotic physics. Potential sources of gravitational waves (GWs) in the nanohertz band include cosmic strings, inflation, and early universe phase transitions. GW observations will also make possible new tests of gravitational theories and provide a means to probe certain dark matter models.
Fundamental Physics with Galactic Center Pulsars, by Geoffrey Bower, ASIAA NASA ADS record: 2019BAAS...51c.438B/abstract Pulsars in the Galactic Center are important probes of General Relativity, star formation, stellar dynamics, and stellar evolution, the ISM, and the supermassive black hole accretion flow. A pulsar in orbit around Sgr A* will characterize black hole physics and GR at sensitivities orders of magnitude better than any other method.
Studying the Reionization Epoch with QSO Absorption Lines, by George Becker, University of California, Riverside NASA ADS record: 2019BAAS...51c.440B/abstract We present opportunities over the coming decade for using QSO absorption lines to study the epoch of reionization. We emphasize the role of optical and near-infrared spectroscopy with ELTs and JWST, and note synergies with QSO surveys, redshifted 21 cm experiments, and galaxy studies with ALMA, JWST, and WFIRST.
Star-Forming Filaments and Cores in Molecular Clouds, by Rachel Friesen, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.441F/abstract Dense, star-forming gas in molecular clouds is dominated by filamentary structures. We describe the best probes of the dynamics of filaments and cores in nearby star-forming molecular clouds, and our recommendations for furthering our understanding of star formation physics through observations over the next decade.
Making Exoplanet Surveys Useful for Statistical Population Studies, by Steve Bryson, NASA Ames Research Center NASA ADS record: 2019BAAS...51c.443B/abstract In this white paper we discuss what kind of information surveys can provide to facilitate statistical analysis that reveals properties of true exoplanet populations. We will gather lessons from various surveys and discuss how diverse and independent surveys can provide data that supports statistical inference. We make several recommendations.
53 of 150, by Nissim Fraija, Instituto de Astronomia, UNAM, Mexico NASA ADS record: 2019astro2020T.444F/abstract In this paper, we review the importance to have a wide field-of-view TeV gamma-ray observatory with a large duty cycle in order to study Active Galactic Nuclei (AGN) phenomena at very-high energies (photons with energies larger than 100 GeV). We focus in blazars, a special sub-class of AGN.
A Strategy for Understanding Planet Formation, by Alycia Weinberger, Carnegie DTM NASA ADS record: 2019BAAS...51c.445W/abstract This white paper argues for a pan-chromatic approach to understanding planet formation including observations from X-rays through radio. Planet formation research seeks to address: where planets form in circumstellar disks, how material is transported through the disk and into planets, and how disks evolve in concert with their stars and planets.
H2O Megamaser Cosmology with the ngVLA, by James Braatz, NRAO NASA ADS record: 2019BAAS...51c.446B/abstract A local measurement of the Hubble Constant at z << 0.5 provides the strongest complement to observations of the CMB for constraining models of dark energy and testing the standard cosmological model. This white paper describes how the ngVLA can contribute to measuring H0 to a precision of one percent using the H2O megamaser method.
Ground-based Observations of Small Solar System Bodies: Probing Our Local Debris Disk, by Amy Lovell, Agnes Scott College NASA ADS record: 2019BAAS...51c.448L/abstract Comets and asteroids are a window into the formation, evolution, and dynamic environment of our solar system, an end-state of debris disks that we can only study from afar. Long-wavelength radio ground-based observations of asteroids and comets provide an excellent complement to shorter-wavelength observations both from the ground and from space.
Energetic Particles of Cosmic Accelerators II: Active Galactic Nuclei and Gamma-ray Bursts, by Tonia Venters, NASA Goddard Space Flight Center NASA ADS record: This white paper is the first of a two-part series highlighting the most well-known high-energy cosmic accelerators and contributions that MeV gamma-ray astronomy will bring to understanding their energetic particle phenomena. This white paper discusses active galactic nuclei and gamma-ray bursts.
A Survey of Hot Gas in the Universe, by Joel Bregman, University of Michigan NASA ADS record: 2019BAAS...51c.450B/abstract A large fraction of the baryons and most of the metals in the Universe remain unaccounted. Their kinematic signatures hold critical insights to the processes of galaxy formation in extended group halos, galaxy groups, and the cosmic web. We present why grating spectrometers are essential instruments for future X-ray missions.
Dust growth and dust trapping in protoplanetary disks with the ngVLA, by Nienke van der Marel, NRC Herzberg Astronomy & Astrophysics programs NASA ADS record: 2019BAAS...51c.451V/abstract ALMA reveals structures in protoplanetary disks that indicate dust trapping as an important mechanism in the planet formation process, but interpretation is limited due to the optically thick mm emission. The next-generation Very Large Array (ngVLA) will open up the possibilities to study dust growth in disks in optically thin cm wavelengths.
Gravitational wave astronomy with LIGO and similar detectors in the next decade, by David Shoemaker, Massachusetts Institute of Technology NASA ADS record: 2019BAAS...51c.452S/abstract We describe the plans for gravitational-wave observations and astrophysics that will be carried out in the next decade using data from the LIGO Observatories in the US and sister facilities abroad. We provide an overview of gravitational wave signal types that we are targeting, and the role of gravitational waves in multi-messenger astronomy.
Gravitational Waves in the Mid-band with Atom Interferometry, by Jason Hogan, Stanford University NASA ADS record: 2019BAAS...51c.453H/abstract We discuss the science possibilities for gravitational wave astronomy in the mid-band frequency range (30 mHz to 10 Hz) in the context of the MAGIS proposal. The discovery potential of such instrumentation appears exciting, ranging from observation of new astrophysical and cosmological sources, as well as searches for ultralight dark matter.
Synergizing Deep Field Programs Across Multiple Surveys, by Peter Capak, California Institute of Technology NASA ADS record: A critical component of many past, present and future astronomical surveys is a dedicated deep field program. We argue these should be explicitly coordinated and considered in project design to maximize the scientific output of these important observations.
Supernova Remnants in High Definition, by Laura Lopez, The Ohio State University NASA ADS record: 2019BAAS...51c.454L/abstract Supernova remnants (SNRs) offer the means to study SN explosions, dynamics, and shocks at sub-parsec scales. In this white paper, we discuss the major advances possible with X-ray spectro-imaging at arcsecond scales, with a few eV spectral resolution and a large effective area.
The state of gravitational-wave astrophysics in 2020, by Sean McWilliams, West Virginia University NASA ADS record: 2019BAAS...51c.455M/abstract We will describe the scientific prospects for the field of gravitational-wave astronomy as a whole as we enter the coming decade, and we will place the specific contributions from a future space-based gravitational-wave observatory within this context.
Measuring the Hubble Constant Near and Far in the Era of ELT's, by Rachael L Beaton, Princeton University NASA ADS record: 2019BAAS...51c.456B/abstract Despite great progress, controversy remains regarding H0. New techniques for measuring H0 have come-of-age in this decade. In the next decade, the combination of ELTs and other ground-based facilities using these techniques will transform measurement of H0. The techniques are described, with a focus on how to realize a 1% measure of H0 with each.
Keeping an Ultraviolet Eye on Supernovae, by Peter Brown, Texas A&M University, Mitchell Institute for Fundamental Physics and Astronomy NASA ADS record: 2019BAAS...51c.457B/abstract Transient astronomy will take another leap forward with the wide-field samples from LSST and WFIRST. It is imperative that we plan for ultraviolet capabilities to maximize our understanding of these explosions, their use as cosmological probes, and for comparisons with high redshift supernovae in the early universe.
41 out of 150, by Nissim Fraija, Instituto de Astronomia, UNAM, Mexico NASA ADS record: 2019astro2020T.459F/abstract In this paper, we review the importance to have a wide field-of-view TeV gamma-ray observatory with a large duty cycle in order to study cosmic rays in the energy range of TeV – PeV.
The Virtues of Time and Cadence for Pulsars and Fast Transients, by RYan Lynch, Green Bank Observatory NASA ADS record: 2019BAAS...51c.461L/abstract We summarize the scientific opportunities that can be realized using pulsars and fast radio transients with high-cadence, long duration observing programs and data sets, with a particular focus on gravitational waves, fundamental physics, pulsar emission, the dynamical interstellar and intergalactic media, and fast radio bursts.
The Mid-Infrared Search for Biosignatures on Temperate M-Dwarf Planets, by Tiffany Kataria, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019astro2020T.462K/abstract In this science white paper, we present the importance of transiting planets in understanding habitability, and how the mid-infrared provides a unique spectroscopic window to the most prominent signatures of life. We recommend the development of a large space-based IR telescope to conduct high-precision spectroscopy over a broad wavelength range.
The Origin of the Elements Across Cosmic Time, by Jennifer Johnson, Ohio State University NASA ADS record: 2019BAAS...51c.463J/abstract This white paper describes the current advances in our understanding of the origin of the elements, lists important outstanding issues, discusses the implications for improving our knowledge, and describes the capabilities needed to make progress over the next decade.
Radio Spectral Line Probe of Evolution of Fundamental Constants, by Tapasi Ghosh, Green Bank Observatory, WV NASA ADS record: Comparisons between the redshifts of multiple spectral transitions from distant galaxies provide a sensitive probe of secular evolution in fundamental constants over cosmological epochs. We summarizes the current status of the field and the directions for progress with large radio telescopes and their new and improved instrumentation.
Planetary Science with Astrophysical Assets: Defining the Core Capabilities of Platforms, by James Bauer, University of Maryland NASA ADS record: We describe a uniform set of basic capabilities to maximize the yield of Solar System science with future Astrophysics assets while allowing those assets to achieve their Astrophysics priorities. Inclusion of capabilities that make a particular platform useable to planetary science provide a critical advantage over platforms lacking them.
Studying the magnetized ISM with all-sky polarimetric radio maps, by Colin Lonsdale, MIT Haystack Observatory NASA ADS record: 2019BAAS...51c.465L/abstract This paper describes the scientific utility of all-sky mapping at low radio frequencies, for improving our understanding of the interstellar medium. With matched resolution across a wide frequency range, precision calibration, and polarimetry, qualitatively new studies of importance will be enabled. The necessary technology is swiftly maturing.
Resolving the cosmic X-ray background with a next-generation high-energy X-ray observatory, by Ryan Hickox, Dartmouth College NASA ADS record: 2019BAAS...51c.468H/abstract We review progress in understanding the high-energy X-ray emission from active galactic nuclei, and highlight exciting opportunities for a future high-resolution, hard (1-200 keV) X-ray observatory to resolve the cosmic X-ray background and characterize accreting supermassive black holes across cosmic time.
Establishing an Empirical Substellar Sequence to Planetary Masses, by Trent Dupuy, Gemini Observatory, Northern Operations NASA ADS record: 2019BAAS...51c.469D/abstract Mass is the most fundamental parameter governing the life-history of all gaseous objects from stars to brown dwarfs and giant planets. Extending measurements of mass to the regime of directly imaged gas-giants, and spectroscopically characterizing this mass sample, will require the leap in angular resolution and sensitivity offered by the ELTs.
Synergizing Deep Field Programs Across Multiple Surveys, by Peter Capak, California Institute of Technology NASA ADS record: 2019BAAS...51c.470C/abstract A critical component of many past, present and future astronomical surveys is a dedicated deep field program. We argue these should be explicitly coordinated and considered in project design to maximize the scientific output of these important observations.
GRBs as Probes of the Early Universe with TSO, by Nial Tanvir, University of Leicester NASA ADS record: 2019BAAS...51c.472T/abstract Long-GRBs are extremely luminous and trace massive star formation to z>8. Afterglow spectroscopy probes host ISM and IGM on the line of sight, providing abundances, average escape fraction and IGM neutral fraction. The proposed Time-domain Spectroscopic Observatory will provide O/IR imaging and spectroscopy for much larger samples of z>6-12 GRBs.
Following the Metals in the Intergalactic and Circumgalactic Medium over Cosmic Time, by Nicolas Lehner, University of Notre Dame NASA ADS record: 2019BAAS...51c.473L/abstract Metal enrichment throughout the universe offers a unique probe of the large-scale gas flows governing galaxy evolution. We argue that fully tracking metals through galaxies, the circumgalactic and intergalactic media will require a large telescope with a FUV/NUV high-resolution spectrograph and science-ready archives for ground-based observatories.
Planetary Habitability Informed by Planet Formation and Exoplanet Demographics, by Daniel Apai, University of Arizona NASA ADS record: 2019BAAS...51c.475A/abstract Many parameters that influence the habitability of a given exoplanet can not be measured. We discuss how can contextual knowledge on exoplanet population and planet formation be combined with uncertain information on individual planets. We review key questions that must be addressed to improve the predictive power of planet formation models.
A Unification of the Micro and Macro Physics in the Intracluster Medium of Nearby Clusters, by Yuanyuan Su, University of Kentucky NASA ADS record: 2019BAAS...51c.476S/abstract The vast bulk of the hot baryons in the Universe is in the form of the intracluster medium. All major cosmological simulations assume the astrophysical plasma to be inviscid. It is critical to constrain the effective transport coefficient of the intracluster medium to truly understand the baryonic processes in the Universe.
Planetary Science with Astrophysical Assets: Defining the Core Capabilities of Platforms, by James Bauer, University of Maryland NASA ADS record: 2019BAAS...51c.477B/abstract We describe a uniform set of basic capabilities to maximize the yield of Solar System science with future Astrophysics assets while allowing those assets to achieve their Astrophysics priorities. Inclusion of capabilities that make a particular platform useable to planetary science provide a critical advantage over platforms lacking them.
Secular Transient Radio Sources, by Christopher Salter, Green Bank Observatory & Arecibo Observatory NASA ADS record: 2019BAAS...51c.479S/abstract The discovery and study of "secular transient radio sources" are reviewed via a number of examples. The continuing major contributions by large single-dish radio telescopes to the discovery, monitoring and VLBI follow-up studies of these transients are highlighted.
Galaxy Winds in the Age of Hyperdimensional Astrophysics, by Grant Tremblay, Center for Astrophysics | Harvard & Smithsonian NASA ADS record: 2019BAAS...51c.480T/abstract Energy feedback has achieved paradigmatic status in the field of galaxy evolution, but many of its key aspects remain unobserved. ALMA and modern IFU spectrographs map galactic winds with unprecedented detail. These observations are equivalent to seeing only sparks in a fire. A next-generation X-ray microcalorimeter is needed to see the flame.
Unique Probes of Reionization with the CMB:From the First Stars to Fundamental Physics, by Marcelo Alvarez, University of California, Berkeley NASA ADS record: 2019BAAS...51c.482A/abstract Much of reionization remains hidden from view, and along with it our understanding of howstars, black holes, and galaxies first emerged. We outline the discoveries enabled by the CMB and highlight the most difficult challenges, including planning and coordination, frequency coverage, angular resolution, and sensitivity.
Binary and Multiple Star Systems at High Angular Resolution, by Gail Schaefer, The CHARA Array of Georgia State University NASA ADS record: 2019BAAS...51c.483S/abstract Binary and multiple star systems provide laboratories for measuring stellar masses and studying star formation, stellar evolution, and dynamical evolution over time. This paper outlines several areas in the context of binary stars that can be advanced over the next decade.
Magnetism in the Brown Dwarf Regime, by Melodie Kao, Arizona State University NASA ADS record: 2019BAAS...51c.484K/abstract A suite of discoveries in the last two decades demonstrate that we are now at a point where incorporating magnetic behavior is key for advancing our ability to characterize substellar systems. Investing now in brown dwarf magnetism will provide a key platform for exploring exoplanetary magnetism and habitability beyond the solar system.
Energetic Particles of Cosmic Accelerators II: Active Galactic Nuclei and Gamma-ray Bursts, by Tonia Venters, NASA Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.485V/abstract This white paper is the first of a two-part series highlighting the most well-known high-energy cosmic accelerators and contributions that MeV gamma-ray astronomy will bring to understanding their energetic particle phenomena. This white paper discusses active galactic nuclei and gamma-ray bursts.
Imaging Entire Molecular Clouds in many Lines: Formation of Stars and Planets, by Jens Kauffmann, Haystack Observatory, Massachusetts Institute of Technology NASA ADS record: 2019BAAS...51c.486K/abstract Studies of molecular line emission at >70 GHz will substantially advance our picture of how stars from in the molecular clouds of the Milky Way. Such work requires spatially resolved imaging of entire clouds at ~0.1 pc resolution. This work requires both small and large telescopes, as well as ALMA.
Exploring the physics of neutron stars with high-resolution, high-throughput X-ray spectroscopy, by Jeremy Heyl, University of British Columbia NASA ADS record: Combining TES detectors with collector optics will also us to study neutron stars in much greater detail by achieving high-energy resolution (1 eV) with much larger collecting areas to uncover even weak spectral features over a wide range of the photon energies. Perhaps we will finally be able to study neutron stars like stars.
Quasar microlensing: Revolutionizing our understanding of quasar structure and dynamics, by Leonidas Moustakas, JPL/Caltech NASA ADS record: 2019BAAS...51c.487M/abstract Microlensing in strong-lens systems with quasars provides a unique detailed view of the internal structure of active black holes to the scale of nano-arcseconds. The case is made for the potential of this approach to revolutionize our understanding of quasar physics and its role in broader questions, with a coherent community strategy.
Stellar Physics and Galactic Archeology using Asteroseismology in the 2020's, by Daniel Huber, Institute for Astronomy, University of Hawaii NASA ADS record: 2019BAAS...51c.488H/abstract Asteroseismology is the only observational tool in astronomy that can probe the interiors of stars, and is a benchmark method for deriving fundamental properties of stars and exoplanets. In this white paper, we describe key science questions and necessary facilities to continue the asteroseismology revolution into the 2020's.
Mass Spectroscopy of the Milky Way, by Arjun Dey, National Optical Astronomy Observatory NASA ADS record: 2019BAAS...51c.489D/abstract Massively multiplexed spectroscopic surveys of Milky Way stars will revolutionize our understanding of our Galaxy's structural components, revealing their past history and the small-scale structure of its dark matter halo. A spectroscopic survey of 10^8 stars, previously unimaginable, is now within reach of new instruments in the coming decade.
Multi-Messenger Astrophysics With Pulsar Timing Arrays, by Luke Kelley, Northwestern University NASA ADS record: 2019BAAS...51c.490K/abstract Pulsar timing arrays are on the verge of detecting low-frequency gravitational waves from supermassive black hole binaries. Multi-messenger observations will revolutionize our understanding of: 1. co-evolution of BHs with their hosts, 2. interactions of binaries with their environments, 3. fundamental physics of accretion, 4. cosmological distances
Exploring the physics of neutron stars with high-resolution, high-throughput X-ray spectroscopy, by Jeremy Heyl, University of British Columbia NASA ADS record: 2019BAAS...51c.491H/abstract Combining TES detectors with collector optics will also us to study neutron stars in much greater detail by achieving high-energy resolution (1 eV) with much larger collecting areas to uncover even weak spectral features over a wide range of the photon energies. Perhaps we will finally be able to study neutron stars like stars.
Twelve Decades: Probing the Interstellar Medium from kiloparsec to sub-AU scales, by Dan R. Stinebring, Oberlin College NASA ADS record: 2019BAAS...51c.492S/abstract After a decade of great progress in understanding gas flow into, out of, and through the Milky Way, we are poised to merge observations with simulations to build a comprehensive picture of the multi-scale magnetized interstellar medium. These insights will also be crucial to four bold initiatives in the 2020s: GWs, FRBs, cosmic B-mode, and the EHT.
The Key Role of Supernova Spectrophotometry in the Next-Decade Dark Energy Science Program, by Saul Perlmutter, UC Berkeley / LBNL NASA ADS record: 2019BAAS...51c.494P/abstract For LSST and WFIRST to together take a major step forward in the SN measurements of dark energy the leading systematics --SN population drift and changes in dust properties-- both must be constrained. This requires space-based instrumentation to provide the wide-wavelength-range spectrophotometry, not just imaging, to measure these two effects.
Time-Domain Photometry of Protostars at Far-Infrared and Submillimeter Wavelengths, by William Fischer, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.495F/abstract The majority of the main-sequence mass of a star is assembled in the protostellar phase, where a forming star is embedded in an infalling envelope and encircled by a protoplanetary disk. We discuss the progress that would be enabled with far-infrared and submillimeter programs to probe protostellar accretion variability in the nearest kiloparsec.
The Demographics and Atmospheres of Giant Planets with the ELTs, by Brendan Bowler, The University of Texas at Austin NASA ADS record: 2019BAAS...51c.496B/abstract Fundamental questions about the system architectures, formation, migration, and atmospheres of giant planets have been unanswerable with the current generation of ground- and space-based facilities. This white paper highlights the scientific potential of the ELTs to address these questions with a focus on direct imaging of Gaia-selected planets.
An Interdisciplinary Perspective on Elements in Astrobiology: From Stars to Planets to Life, by Natalie Hinkel, Southwest Research Institute NASA ADS record: 2019BAAS...51c.497H/abstract Stellar elemental abundances directly impact planetary interiors, surface composition, and life. However, communities necessary for habitability (astrophysics, planetary science, geology, biology) emphasize different elements. We must broaden our communication regarding lists of useful elements and how they can be observed in the near and long term
Imaging the Key Stages of Planet Formatio, by John Monnier, University of Michigan NASA ADS record: 2019BAAS...51c.498M/abstract In this white paper, we explore how higher angular resolution beyond ALMA and 8m-class telescopes can extend our understanding of the key stages of planet formation, to resolve accreting circumplanetary disks themselves, and to watch planets forming in situ for the nearest star-forming regions.
The Cusp of Discovery in Astronomy, by Nicholas B. Suntzeff, Mitchell Institute for Fundamental Physics & Astronomy, Texas A&M University NASA ADS record: 2019BAAS...51c.499S/abstract In this white paper, I call upon our community to organize our goals behind the theme to discover life elsewhere in the Universe in the next decade.
Spatially-resolved studies of star-forming galaxies in the reionization epoch, by Swara Ravindranath, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.500R/abstract Spatially-resolved emission line studies of reionization sources probing few 10-100s parsecs is key to understanding the earliest phases of galaxy assembly, growth of seed black holes, and formation of proto-globular cluster. High spatial resolution (<100 mas), high spectral resolution (R>4000), and high sensitivity are necessary to make progress.
Imaging Entire Molecular Clouds in many Lines: From the Milky Way to Galaxies, by Jens Kauffmann, Haystack Observatory, Massachusetts Institute of Technology NASA ADS record: 2019BAAS...51c.501K/abstract Emission lines from molecules at frequencies >70 GHz allow astronomy to explore how star formation depends on molecular cloud conditions, and how cloud conditions vary within galaxies. However, comprehensive observations of the Milky Way are needed to refine lines as probes of gas conditions. Such work requires both large and small telescopes.
High Angular Resolution Astrophysics in the Era of Time Domain Surveys, by Gail Schaefer, The CHARA Array of Georgia State University NASA ADS record: 2019BAAS...51c.502S/abstract Over the next decade, all-sky photometric surveys will dramatically increase the number of time variable objects discovered. Long-baseline optical interferometry has the power to resolve the spatial structure of bright transients like the early stages of novae explosions, Be star outbursts, and gravitational microlensing.
Precision Stellar Astrophysics and Galactic Archeology: 2020, by Juna Kollmeier, Carnegie Institution for Science NASA ADS record: 2019BAAS...51c.503K/abstract This white paper is meant to capture many different elements of stellar astrophysics and galactic archeology that highlight the important role this science will play in the 2020s era of precision astronomy.
Black Hole Growth in Mergers and Dual AGN, by Michael Koss, Eureka Scientific NASA ADS record: 2019astro2020T.504K/abstract Galaxy mergers are predicted to represent a significant stage of SMBH growth. This white paper discusses the key questions in galaxy mergers, dual, and offset AGN, and proposes solutions using future high-resolution multiwavelength observatories in the X-rays (AXIS, Lynx), NIR and MIR (JWST and 30-meter class telescopes), and submillimeter (ALMA).
Wide-Orbit Exoplanet Demographics, by David Bennett, NASA Goddard and University of Maryland NASA ADS record: 2019BAAS...51c.505B/abstract There is currently a gap in our understanding of wide-orbit planets, which must be filled if we are to understand planet formation and exoplanet habitability. We summarize current and planned exoplanet detection programs using a variety of methods: microlensing (including WFIRST), radial velocities, Gaia astrometry, and direct imaging.
Determining the Equation of State of Cold, Dense Matter with X-ray Observations of Neutron Stars, by Slavko Bogdanov, Columbia University NASA ADS record: 2019BAAS...51c.506B/abstract X-ray observations from multiple next-generation X-ray telescopes proposed for deployment in the 2020s and beyond, using several complementary techniques that require different combinations of high time resolution, superb spectral resolution, and high spatial resolution can provide definitive constraints on the state of cold, ultra-dense matter.
IGM and CGM Emission Mapping: A New Window on Galaxy and Structure Formation, by Christopher Martin, California Institute of Technology NASA ADS record: 2019BAAS...51c.510M/abstract We describe the prospects for IGM and CGM emission mapping with UV resonance lines at low and high redshift. There are 5 key science questions that will be addressed: 1) A Lyman alpha emission calibration; 2) physical properties of galaxy halos; 3) the role and nature of gas inflows to galaxies; 4) gas outflows: 5) emission from the cosmic web.
Optimal Architectures and Survey Designs for Maximizing the Yields of Direct-Imaging Exoplanet Missions, by Christopher Stark, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.511S/abstract Our ability to answer scientific questions about exoplanets hinges on satisfying an age-old astronomical requirement: a sufficient sample size. Thus, the yield of exoplanets is critical to understanding the scientific impact of future missions. We discuss how the yield of directly-imaged exoplanets depends on mission scale and survey design.
The Future of Exoplanet Direct Detection, by John Monnier, University of Michigan NASA ADS record: 2019BAAS...51c.514M/abstract Diffraction fundamentally limits our ability to image and characterize exoplanets. Interferometry offers some advantages in exoplanet detection and characterization and we explore in this white paper some of the potential scientific breakthroughs possible.
Extremely obscured galaxy nuclei – hidden AGNs and extreme starbursts, by Susanne Aalto, Chalmers University of Technology, Sweden NASA ADS record: 2019BAAS...51c.515A/abstract Understanding the evolution of galaxies and galaxy nuclei requires studying the extremely obscured activity that has recently been uncovered using submm facilities. Properly interpreting these observations requires advances in the radio, mm/submm, far-infrared and X-ray facilities than can peer through the obscuration.
Testing general relativity with accretion onto compact objects, by Ilaria Caiazzo, University of British Columbia NASA ADS record: 2019BAAS...51c.516C/abstract The X-ray emission of neutron stars and black holes presents a rich phenomenology that can help us answer: Does general relativity apply in the strong gravity regime? Are black holes described by the Kerr metric? We consider how to investigate these questions with a combination of high-spectral and high-timing resolution using TES arrays.
Direct Imaging of Exoplanets in Nearby Multi-Star Systems, by Ruslan Belikov, NASA Ames Research Center NASA ADS record: 2019BAAS...51c.517B/abstract Binary star systems can enhance the science output of almost any space mission that directly images exoplanets, if the technologies to suppress starlight in multi-star systems are matured. We describe the science benefits and opportunities of adding binary stars to such missions, as well as the key technology advances needed.
From Interstellar Ice Grains to Evolved Planetary Systems: The Role of Laboratory Studies, by Murthy Gudipati, Jet Propulsion Laboratory, California Institute of Technology NASA ADS record: 2019BAAS...51c.518G/abstract Laboratory studies that are directed towards understanding how simple astrophysical molecules evolve and how complex molecules are produced, preserved, and transported from interstellar conditions through the protoplanetary phase to an evolved planetary system. We emphasize the status of current laboratory research and future needs.
Masses and Distances of Planetary Microlens Systems with High Angular Resolution Imaging, by Aparna Bhattacharya, University of Maryland College Park NASA ADS record: 2019BAAS...51c.520B/abstract Microlenisng is only method to detect and measure mass of wide orbit, low mass, solar system analog planets. Mass measurements of these planets vis high res obs yield massive science. We show that high res obs with AO, HST and JWST remain necessary to enhance the scientific yield of WFIRST microlensing survey.
Towards a Theory for Star Formation on All Scales, by Eric Murphy, National Radio Astronomy Observatory NASA ADS record: 2019BAAS...51c.523M/abstract This white paper focusses on resolved studies of star formation within large samples of nearby galaxies using diagnostics that are unbiased by dust, and can measure star formation activity over the full range of scales and galaxy environments that it operates.
Invisible Structures in the Local Universe, by Robert Minchin, USRA NASA ADS record: 2019BAAS...51c.524M/abstract Neutral hydrogen surveys have revealed the existence of dark and almost-dark structures around nearby galaxies and in local groups and clusters. Understanding these structures will give us insights into how hydrogen cycles in and out of galaxies in different environments and will help us to understand the occupancy of low-mass dark matter subhalos.
The Nature of Low-Density Star Formation, by David Thilker, Johns Hopkins University NASA ADS record: 2019BAAS...51c.525T/abstract How do stars manage to form within low-density, HI-dominated gas? Here we outline fundamental questions about the nature of star formation at low-density. We describe the wide-field, high-resolution imaging of stars, star clusters, and gas clouds in nearby galaxies needed to provide definitive answers and build a complete theory of star formation.
Imaging Giant Protoplanets with the ELTs, by Steph Sallum, University of California, Santa Cruz NASA ADS record: 2019BAAS...51c.527S/abstract Constraining the details of giant planet formation requires building a census of forming planets and characterizing protoplanetary disks. This whitepaper describes the scientific progress in observational planet formation studies that will be made possible by instrumentation advances during the next decade.
Life Beyond the Solar System: Remotely Detectable Biosignatures, by Shawn Domagal-Goldman, NASA Goddard Space Flight Center NASA ADS record: 2019astro2020T.528D/abstract This white paper reviews the scientific community's ability to use data from future telescopes to search for life on exoplanets. It summarizes products from the Exoplanet Biosignatures Workshop Without Walls (EBWWW). This effort led to papers that constituted the Exoplanet Analysis Group's (ExoPAG) 16th Science Assessment Group (SAG 16).
Probing the Time Domain with High Spatial Resolution, by John Blakeslee, Gemini Observatory NASA ADS record: 2019BAAS...51c.529B/abstract This white paper discusses science opportunities enabled at the interface of JWST and LSST, that is, at the frontier of high spatial resolution time-domain optical-IR astronomy. It describes the capabilities of a practical system that would maximize the science return in this area.
Multi-Messenger Astrophysics Opportunities with Stellar-Mass Binary Black Hole Mergers, by Peter Shawhan, University of Maryland and Joint Space-Science Institute NASA ADS record: 2019BAAS...51c.531S/abstract It is often thought that stellar-mass binary black hole mergers should not produce a detectable electromagnetic transient. However, there ARE a number of mechanisms for producing such a counterpart. We review these, and the astrophysics and fundamental physics we can learn from detecting or constraining them.
Detecting Metal-Free Forming Galaxies at High Redshift, by Eiichi Egami, Steward Observatory, University of Arizona NASA ADS record: 2019astro2020T.532E/abstract The next frontier in the study of high-redshift galaxies is the detection of the first-generation ``forming'' galaxies that are emerging out of metal-free gas clouds at the end of the cosmic dark ages. Here, we discuss the detectability of such metal-free forming galaxies at high redshift.
Ultraviolet Perspectives on Diffuse Gas in the Largest Cosmic Structures, by Joseph Burchett, Univ. of California - Santa Cruz NASA ADS record: 2019BAAS...51c.534B/abstract In this White Paper, we highlight key science cases where UV spectroscopy will provide unique insights into the most massive structures in the Universe, and we discuss how current (HST/COS) and future (LUVOIR) missions can deliver transformative understanding of galaxy evolution, galaxy cluster physics, and gas within the Cosmic Web.
Lyman continuum observations across cosmic time: recent developments, future requirements, by Stephan McCandliss, Johns Hopkins University NASA ADS record: 2019BAAS...51c.535M/abstract Quantifying the physical conditions that allow radiation emitted shortward of the hydrogen ionization edge at 911.7 Ã… to escape the first collapsed objects and ultimately reionize the universe is a compelling problem for astrophysics. Multi-object spectroscopy from facility class telescopes are required.
Spatially Resolved Observations of the Ultraviolet Attenuation Curve, by Lea Hagen, STScI NASA ADS record: 2019BAAS...51c.536H/abstract UV attenuation curves are used to correct rest-frame UV galaxy fluxes, and they encode information about dust-star geometry and dust grain properties. Spatially resolved measurements of the UV attenuation curve in the local universe will enable better constraints on corrections, dust geometry, and dust grains across all redshifts.
Black Hole Physics on Horizon Scales, by Sheperd Doeleman, Center for Astrophysics | Harvard and Smithsonian NASA ADS record: 2019BAAS...51c.537D/abstract High-resolution imaging of supermassive black holes can test general relativity and elucidate processes of accretion/jet formation on scales of the event horizon. Enhancements achievable within the decade would provide high-fidelity, time-resolved observations of Sgr A*, M87, and other black holes, enabling breakthroughs in black hole astrophysics.
Observing Galaxy Evolution in the Context of Large-Scale Structure, by Mark Dickinson, NOAO NASA ADS record: 2019BAAS...51c.538D/abstract Galaxies form and evolve in the context of their large-scale environments. Very large spectroscopic surveys (e.g., SDSS, GAMA) have been invaluable for quantifying this connection in the local universe. We consider advances in understanding galaxy evolution that would be enabled by very large, high-density spectroscopic surveys at high redshifts.
Planetary Radar Astronomy with Ground-Based Astrophysical Assets, by Patrick Taylor, Lunar and Planetary Institute NASA ADS record: 2019BAAS...51c.539R/abstract Galaxies form and evolve in the context of their large-scale environments. Very large spectroscopic surveys (e.g., SDSS, GAMA) have been invaluable for quantifying this connection in the local universe. We consider advances in understanding galaxy evolution that would be enabled by very large, high- density spectroscopic surveys at high redshifts.
Solar system Deep Time-Surveys of atmospheres, surfaces, and rings, by Michael H. Wong, UC Berkeley NASA ADS record: 2019BAAS...51c.541W/abstract Imaging and resolved spectroscopy reveal varying environmental conditions in our dynamic solar system. Observatory-level commitments to conduct annual observations of solar system bodies would establish a long-term legacy chronicling the evolution of dynamic planetary atmospheres, surfaces, and rings.
Type Ia Supernova Cosmology with TSO, by Michael Wood-Vasey, University of Pittsburgh NASA ADS record: 2019BAAS...51c.543W/abstract Space-based 1--2.5~m class observatories with imaging and spectroscopic instruments covering $0.3<\lambda<4.5$~$\mu$m offer significant opportunities to advance Type Ia supernova cosmology. We here focus on the Time-domain Spectroscopic Observatory to observe Type Ia Supernova from 0.3--4.5 um with both imaging and spectroscopic capabilities.
The Chemical/Dynamical Evolution of the Galactic Bulge, by R. Michael Rich, Department of Physics and Astronomy, UCLA NASA ADS record: 2019BAAS...51c.544R/abstract This paper points out several current problems in the study of the Galactic bulge, such as the age and structure problems, and advocates high resolution, high S/N, optical spectroscopy of the bulge as enabled by facilities being planned in the next decade.
Walking along Cosmic History: Metal-poor Massive Stars, by Miriam Garcia, Centro de Astrobiologia, CSIC-INTA NASA ADS record: 2019BAAS...51c.545G/abstract This paper proposes to supersede the SMC standard with a new metallicity ladder built from very metal-poor galaxies, and provides a brief overview of the technological facilities needed to this aim.
Extremely metal-poor stars: the need for UV spectra, by Piercarlo Bonifacio, GEPI, Observatoire de Paris NASA ADS record: 2019BAAS...51c.546B/abstract Extremely metal-poor stars are the fossil record of the gas in the pristine Universe. They offer us the opportunity to understand the mass distribution and nucleosynthetic properties of the First generation of stars. UV spectra provide access to information not available in other spectral ranges.
High-Resolution Spectroscopic Surveys of Ultracool Dwarf Stars & Brown Dwarfs, by Adam Burgasser, UC San Diego NASA ADS record: 2019BAAS...51c.547B/abstract High resolution spectroscopy of the lowest-mass stars and brown dwarfs reveals their origins, multiplicity, compositions and physical properties, with implications for the star formation and chemical evolution history of the Milky Way. We motivate the need for high-resolution, infrared spectroscopic surveys to reach theses faint sources.
Big Science with a nUV-MidIR Rapid-Response 1.3m Telescope at L2, by Jonathan Grindlay, Harvard University NASA ADS record: 2019BAAS...51c.548G/abstract Fundamental Questions in Astrophysics can be addressed by a space telescope designed for rapid-response broad band imaging and spectroscopy. A brief description of the Time-domain Spectroscopic Observatory, a Probe-Class mission for L2, is given.
Ultra Deep Field Science with WFIRST, by Anton Koekemoer, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.550K/abstract This whitepaper motivates an Ultra-Deep Field survey with WFIRST, covering at least ~100x the area of the HUDF, up to ~1 sq deg, to mag ~30, potentially revealing thousands of galaxies and AGN at the faint end of the LF, at or beyond z~10 in the epoch of reionization, and dramatically increasing the discovery potential at these redshifts.
The Search for Life Elsewhere as a Compelling Science Theme for Astro2020, by Ken Sembach, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.551S/abstract We review the evolving science drivers underpinning the search for life elsewhere, as articulated in our own decadal surveys in years past. We also review other documents, and provide a brief digression that considers a philosophy of addressing cost. Our hope is to set the stage for concluding the initial phase of the search for life.
Multi-messenger and transient astrophysics with very-high-energy gamma rays, by Justin Vandenbroucke, University of Wisconsin NASA ADS record: 2019BAAS...51c.553V/abstract The discoveries of high-energy astrophysical neutrinos and of gravitational waves, as well as the rise of time-domain astronomy, have revolutionized astrophysics. We describe the prospects for gamma-ray telescopes, particularly in the energy range greater than 20 GeV, for multi-messenger and transient astrophysics in the decade ahead.
Infrared Stellar Populations: Probing the Beginning and the End, by Margaret Meixner, Space Telescope Science Institute NASA ADS record: 2019BAAS...51c.554M/abstract The early and late stages of star formation and star death remain puzzles. Results from Spitzer and Herschel on the Magellanic Clouds demonstrated the power of infrared stellar populations. We need to do similar studies of galaxies in the local volume and go fainter in the Magellanic Clouds. JWST, and far-infrared observations will be needed.
Understanding Cosmic Evolution: The Role of UV Spectroscopic and Imaging Surveys, by Sara Heap, Emerita scientist, Goddard Space Flight Center NASA ADS record: 2019BAAS...51c.555H/abstract A Probe-class ultraviolet (UV) telescope having capabilities not available to Hubble can help answer many outstanding Key Science Questions posed by Astro2010. Measurements of the processed UV data will increase the scientific yield and impact of this telescope.
Space-Based Measurements of G, by Brian D'Urso, Montana State University NASA ADS record: 2019BAAS...51c.556D/abstract The Newtonian Constant of Gravitation is among the most poorly measured fundamental constants in physics. We review recent measurements of G and propose a new space-based measurement of G in low earth orbit.
Electromagnetic Window into the Dawn of Black Holes, by Zoltan Haiman, Columbia University NASA ADS record: 2019BAAS...51c.557H/abstract The origin of massive black holes in the early universe is one of the major puzzles in astrophysics. Future X-ray surveys can detect BHs with mass M<10^5 Msun at z>10, and OIR observations can characterize their immediate environment. These observations will open a window into the "Dawn of Black Holes" and distinguish models of their origin.
Observing the Earth as a Communicating Exoplanet, by Julia DeMarines, University of California, Berkeley NASA ADS record: 2019BAAS...51c.558D/abstract This white paper highlights an observing project that aims to advance and refine our search for life in the Universe, measure the Earth's technosignature over time, and foster collaborations between radio astronomers and the wider astrobiology community. This paper highlights the Moonbounce Project and opportunities for project expansion.
The Super-Earth Opportunity — Search for Habitable Exoplanets in the 2020s, by Renyu Hu, Jet Propulsion Laboratory NASA ADS record: 2019BAAS...51c.559H/abstract The science return of detecting temperate exoplanets as large as 2 Re should be considered as one of the primary evaluation criteria to assess exoplanet missions. Given the implications on the size of space telescopes, this evaluation criteria should be applied independently from the assessment of capability to find a true Earth analog.
Astrophysics with the NASA Infrared Telescope Facility, by John Rayner, IRTF/University of Hawaii NASA ADS record: 2019BAAS...51c.560R/abstract Much frontline astronomical research can still be done on 3-4-m class optical-infrared telescopes. This paper highlights future key observing that can be efficiently done on IRTF by exploiting current and planned capabilities.
The Importance of Synoptic Solar Radio Observations, by Stephen White, Air Force Research Laboratory NASA ADS record: 2019BAAS...51c.562W/abstract The long history of monitoring the Sun's radio flux has led to time series of solar activity that reflect the solar cycle and the physical nature of solar radio emission. Here we discuss some of the results of this monitoring and the importance of maintaining this record.
Reconstructing Extreme Space Weather From Planet Hosting Stars, by Vladimir Airapetian, NASA GSFC and American University, DC NASA ADS record: 2019BAAS...51c.564A/abstract The goal of this white paper is to identify and describe promising key research goals to aid the theoretical characterization and observational detection of ionizing radiation from quiescent and flaring upper atmospheres of planet hosts as well as properties of stellar coronal mass ejections (CMEs) and stellar energetic particle (SEP) events.
A Plasma-Physical Understanding of Pulsar Radio Emission Physics, by Joanna Rankin, University of Vermont NASA ADS record: 2019BAAS...51c.565R/abstract The paper treats the longstanding problem of understanding pulsar radiation physically. It reports on progress in understanding both the radio and thermal X-ray emission, observationally and theoretically. It argues that recent progress has placed the emission problem on a plasma physics basis and that new efforts will have broad consequences.
Cold Debris Disks as Strategic Targets for the 2020s, by John Debes, STScI NASA ADS record: 2019BAAS...51c.566D/abstract Cold debris disks (T<200 K) are analogues to the dust in the Solar System's Kuiper belt. We lay out a critical path for the study of debris disks that focuses on defining an empirical relationship between scattered light and thermal emission, probing the dynamics and properties of disks, and directly determining planet disk interactions.
Gravitational probes of ultra-light axions, by Daniel Grin, Haverford College NASA ADS record: 2019BAAS...51c.567G/abstract We summarize the high-energy theoretical and astrophysical motivation for ultra-light axions. We summarize observational signatures and possibilities for the next decade, and make recommendations for future theoretical and observational work.
Completing the Hydrogen Census in the Circumgalactic Medium at z~0, by D.J. Pisano, West Virginia University NASA ADS record: 2019BAAS...51c.568P/abstract A description of the contributions of 21cm emission observations with single-dish telescopes to understanding the CGM of galaxies and accretion processes. Supporting interferometric UV absorption line observations are also discussed.
Exploring Dark Energy and Gravity in Space Laboratories, by Nan Yu, Jet Propulsion Laboratory NASA ADS record: 2019astro2020T.570Y/abstract Dark energy is one of the greatest mysteries in science today and has the potential for discovery of new physics. Precision space laboratory experiments provide opportunities for direct detection of dark energy as well as help addressing other outstanding science questions in the area of gravity including dark matter and gravitational waves.
Radio Spectral Line Probe of Evolution of Fundamental Constants, by Tapasi Ghosh, Green Bank Observatory, WV NASA ADS record: 2019BAAS...51c.571G/abstract Comparisons between the redshifts of multiple spectral transitions from distant galaxies provide a sensitive probe of evolution in fundamental constants such as the fine structure constant and the proton-electron mass ratio over cosmological epochs. Here, we the summarize the current status & the directions for progress with large radio telescopes.
High Definition Astrometry, by Philip Horzempa, LeMoyne College NASA ADS record: 2019BAAS...51c.572H/abstract High Definition Astrometry (0.1 - 1.0 micro-arcseconds) will open a new window into neighboring planetary systems. The realm of temperate terrestrial worlds can be surveyed. This includes Earth Analogs, thereby allowing the value of eta-Earth to be directly determined. It will be able to confirm the existence of Radial Velocity (RV) planets.
Relativistic Jets in the Accretion & Collimation Zone: New Challenges Enabled by New Instruments, by Eric Perlman, Florida Institute of Technology NASA ADS record: 2019BAAS...51c..59P/abstract We point out advances that can be achieved by new technology in the zone where AGN jets are accelerated to relativistic speeds and collimated. The ngVLA, near-IR, near-IR, optical and X-ray interferometry, and other projects can produce fundamental advances in understanding jet production, acceleration, collimation and high-energy phenomena.
Kiloparsec-scale Jets: Physics, Emission Mechanisms, and Challenges, by Eric Perlman, Florida Institute of Technology NASA ADS record: 2019BAAS...51c..16P/abstract AGN Jets transport material and energy from sub-pc central regions out beyond their host galaxies. Many issues remain for kpc-scale jets, from dynamics and their interaction with surrounding media to particle acceleration and high-energy emission mechanism. We concentrate on the advances that can be made by new missions and technologies.