Search Publications
Possible X-Ray Quasi-periodic Eruptions in a Tidal Disruption Event Candidate
Miniutti, Giovanni; Kara, Erin; Giustini, Margherita +3 more
X-ray quasi-periodic eruptions (QPEs) are a recently discovered phenomenon associated with supermassive black holes at the centers of galaxies. They are high-amplitude soft X-ray flares that recur on timescales of hours, but what causes these flares remains uncertain. In the two years since their original discovery, four known QPE-hosting galaxies…
I Spy Transits and Pulsations: Empirical Variability in White Dwarfs Using Gaia and the Zwicky Transient Facility
Hermes, J. J.; Bell, Keaton J.; Montgomery, M. H. +13 more
We present a novel method to detect variable astrophysical objects and transient phenomena using anomalous excess scatter in repeated measurements from public catalogs of Gaia DR2 and Zwicky Transient Facility (ZTF) DR3 photometry. We first provide a generalized, all-sky proxy for variability using only Gaia DR2 photometry, calibrated to white dwa…
AGN STORM 2. I. First results: A Change in the Weather of Mrk 817
Gorjian, Varoujan; Treu, Tommaso; Kaspi, Shai +71 more
We present the first results from the ongoing, intensive, multiwavelength monitoring program of the luminous Seyfert 1 galaxy Mrk 817. While this active galactic nucleus was, in part, selected for its historically unobscured nature, we discovered that the X-ray spectrum is highly absorbed, and there are new blueshifted, broad, and narrow UV absorp…
The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) Survey Design, Reductions, and Detections
Ono, Yoshiaki; Ouchi, Masami; Papovich, Casey +60 more
We describe the survey design, calibration, commissioning, and emission-line detection algorithms for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). The goal of HETDEX is to measure the redshifts of over a million Lyα emitting galaxies between 1.88 < z < 3.52, in a 540 deg2 area encompassing a comoving volume of 10.9 …
A Comparative Study of Atmospheric Chemistry with VULCAN
Heng, Kevin; Tsai, Shang-Min; Kitzmann, Daniel +4 more
We present an update of the open-source photochemical kinetics code VULCAN to include C-H-N-O-S networks and photochemistry. The additional new features are advection transport, condensation, various boundary conditions, and temperature-dependent UV cross sections. First, we validate our photochemical model for hot Jupiter atmospheres by performin…
Stars with Photometrically Young Gaia Luminosities Around the Solar System (SPYGLASS). I. Mapping Young Stellar Structures and Their Star Formation Histories
Rizzuto, Aaron C.; Kraus, Adam L.; Offner, Stella S. R. +1 more
Young stellar associations hold a star formation record that can persist for millions of years, revealing the progression of star formation long after the dispersal of the natal cloud. To identify nearby young stellar populations that trace this progression, we have designed a comprehensive framework for the identification of young stars and use i…
A High-resolution View of Fast Radio Burst Host Environments
Kilpatrick, Charles D.; Simha, Sunil; Prochaska, J. Xavier +12 more
We present Hubble Space Telescope ultraviolet and infrared observations of eight fast radio burst (FRB) host galaxies with subarcsecond localizations, including the hosts of three known repeating FRBs. We quantify their spatial distributions and locations with respect to their host galaxy light distributions, finding that they occur at moderate ho…
Gaia EDR3 Proper Motions of Milky Way Dwarfs. I. 3D Motions and Orbits
Hammer, Francois; Babusiaux, Carine; Du, Cuihua +5 more
Based on Gaia Early Data Release 3 (EDR3), we estimate the proper motions of 46 dwarf galaxies of the Milky Way (MW). The uncertainties in proper motions, determined by combining both statistical and systematic errors, are smaller by a factor of 2.5 when compared with Gaia Data Release 2. We have derived orbits in four MW potential models that are…
Orbital Clustering Identifies the Origins of Galactic Stellar Streams
Conroy, Charlie; Ting, Yuan-Sen; Cargile, Phillip A. +9 more
The origins of most stellar streams in the Milky Way are unknown. With improved proper motions provided by Gaia EDR3, we show that the orbits of 23 Galactic stellar streams are highly clustered in orbital phase space. Based on their energies and angular momenta, most streams in our sample can plausibly be associated with a specific (disrupted) dwa…
Kinematics of Antlia 2 and Crater 2 from the Southern Stellar Stream Spectroscopic Survey (S5)
Lewis, Geraint F.; Erkal, Denis; Belokurov, Vasily +15 more
We present new spectroscopic observations of the diffuse Milky Way satellite galaxies Antlia 2 and Crater 2, taken as part of the Southern Stellar Stream Spectroscopic Survey (S5). The new observations approximately double the number of confirmed member stars in each galaxy and more than double the spatial extent of spectroscopic observ…