183 citations · 1.4k across the 36 of their papers we have counts for
37 papers
Early Exploration of the Scientific Discovery Space for the Habitable Worlds Observatory
Courtney D. Dressing, Danica Adams, Evelyne Alecian +324
The Habitable Worlds Observatory (HWO) is a future NASA flagship mission concept identified by the Astro2020 Decadal Survey as the highest priority for large space missions. HWO sh…
Asymmetric nightside CO2 features, inefficient heat transport, and precise evolutionary constraints: Spectroscopic phase curves reveal the past and present of a white dwarf-brown dwarf binary
Daphne Broski-Laing, Yifan Zhou, Joshua D. Lothringer +10
We present the first JWST phase curve of a white dwarf-brown dwarf binary, a NIRSpec PRISM observation of ZTFJ0038+2030. Short-period white dwarf-brown dwarf binaries provide uniqu…
High Velocity Circumstellar Gas Orbiting a White Dwarf Star
B. Zuckerman, Érika Le Bourdais, Beth L. Klein +6
Numerous white dwarf stars are known to be orbited by disks of gas and dust. To date, broad, about 300 km s-1 wide, gaseous circumstellar absorption features have only been reporte…
Modeling Circumstellar Gas Emission around a White Dwarf Using Cloudy
Siyi Xu, Sherry Yeh, Laura. K. Rogers +9
The chemical composition of an extrasolar planet is fundamental to its formation, evolution and habitability. In this study, we explore a new way to measure the chemical compositio…
WD0141-675: A case study on how to follow-up astrometric planet candidates around white dwarfs
Laura K. Rogers, John Debes, Richard J. Anslow +22
This work combines spectroscopic and photometric data of the polluted white dwarf WD0141-675 which has a now retracted astrometric super-Jupiter candidate and investigates the most…
TTV Constraints on Additional Planets in the WD 1856+534 system
Sarah Kubiak, Andrew Vanderburg, Juliette Becker +4
WD 1856+534 b (or WD 1856 b for short) is the first known transiting planet candidate around a white dwarf star. WD 1856 b is about the size of Jupiter, has a mass less than about…
New chondritic bodies identified in eight oxygen-bearing white dwarfs
Alexandra E. Doyle, Beth L. Klein, Patrick Dufour +8
We present observations and analyses of eight white dwarf stars that have accreted rocky material from their surrounding planetary systems. The spectra of these helium-atmosphere w…
Discovery of a resolved white dwarf-brown dwarf binary with a small projected separation: SDSS J222551.65+001637.7AB
Jenni R. French, Sarah L. Casewell, Trent J. Dupuy +4
We present the confirmation of SDSS J222551.65+001637.7AB as a closely separated, resolved, white dwarf-brown dwarf binary. We have obtained spectroscopy from GNIRS and seeing-limi…
MAROON-X: The first two years of EPRVs from Gemini North
Andreas Seifahrt, Jacob L. Bean, David Kasper +11
MAROON-X is a fiber-fed, optical EPRV spectrograph at the 8-m Gemini North Telescope on Mauna Kea, Hawai'i. MAROON-X was commissioned as a visiting instrument in December 2019 and…
wdwarfdate: A Python Package to Derive Bayesian Ages of White Dwarfs
Rocio Kiman, Siyi Xu, Jacqueline K. Faherty +5
White dwarfs have been successfully used as cosmochronometers in the literature, however their reach has been limited in comparison to their potential. We present wdwarfdate, a pub…
No evidence for a strong decrease of planetesimal accretion in old white dwarfs
Simon Blouin, Siyi Xu
A large fraction of white dwarfs are accreting or have recently accreted rocky material from their planetary systems, thereby polluting their atmospheres with elements heavier than…
Polluted White Dwarfs Reveal Exotic Mantle Rock Types on Exoplanets in our Solar Neighborhood
Keith D. Putirka, Siyi Xu
Prior studies have hypothesized that some polluted white dwarfs record continent-like granitic crust--which is abundant on Earth and perhaps uniquely indicative of plate tectonics.…
Exogeology from Polluted White Dwarfs
Siyi Xu, Amy Bonsor
It is difficult to study the interiors of terrestrial planets in the Solar System and the problem is magnified for distant exoplanets. However, sometimes nature is helpful. Some pl…
A Characterization of the Circumstellar Gas around WD 1124-293 using Cloudy
Amy Steele, John Debes, Siyi Xu +2
Between 30 - 50% of white dwarfs (WDs) show heavy elements in their atmospheres. This "pollution" is thought to arise from the accretion of planetesimals perturbed by outer planet(…
A Giant Planet Candidate Transiting a White Dwarf
Andrew Vanderburg, Saul A. Rappaport, Siyi Xu +61
Astronomers have discovered thousands of planets outside the solar system, most of which orbit stars that will eventually evolve into red giants and then into white dwarfs. During…
H--He collision-induced satellite in the Lyman- profile of DBA white dwarf stars
Nicole F. Allard, John F. Kielkopf, Siyi Xu +6
The spectra of helium-dominated white dwarf stars with hydrogen in their atmosphere present a distinctive broad feature centered around 1160~Å\/ in the blue wing of the Lyman- l…
Modeling of the Variable Circumstellar Absorption Features of WD 1145+017
M. Fortin-Archambault, P. Dufour, S. Xu
We present an eccentric precessing gas disk model designed to study the variable circumstellar absorption features detected for WD 1145+017, a metal polluted white dwarf with an ac…
Compositions of Planetary Debris around Dusty White Dwarfs
Siyi Xu, Patrick Dufour, Beth Klein +5
The photospheres of some white dwarfs are "polluted" by accretion of material from their surrounding planetary debris. White dwarfs with dust disks are often heavily polluted and h…
Chemical composition of the outer halo globular cluster Palomar 15
Andreas Koch, Siyi Xu, R. Michael Rich
Globular clusters (GCs) in the outer Milky Way halo are important tracers of the assembly history of our Galaxy. Only a few of these objects show spreads in heavier elements beyond…
Astro 2020 Science White Paper: Evolved Planetary Systems around White Dwarfs
Boris Gaensicke, Martin Barstow, Amy Bonsor +25
Practically all known planet hosts will evolve into white dwarfs, and large parts of their planetary systems will survive this transition - the same is true for the solar system be…
The Detailed Science Case for the Maunakea Spectroscopic Explorer, 2019 edition
The MSE Science Team, Carine Babusiaux, Maria Bergemann +258
(Abridged) The Maunakea Spectroscopic Explorer (MSE) is an end-to-end science platform for the design, execution and scientific exploitation of spectroscopic surveys. It will unvei…
A planetesimal orbiting within the debris disc around a white dwarf star
Christopher J. Manser, Boris T. Gänsicke, Siegfried Eggl +29
Many white dwarf stars show signs of having accreted smaller bodies, implying that they may host planetary systems. A small number of these systems contain gaseous debris discs, vi…
Stellar Astrophysics and Exoplanet Science with the Maunakea Spectroscopic Explorer (MSE)
Maria Bergemann, Daniel Huber, Vardan Adibekyan +70
The Maunakea Spectroscopic Explorer (MSE) is a planned 11.25-m aperture facility with a 1.5 square degree field of view that will be fully dedicated to multi-object spectroscopy. A…
Distant White Dwarfs in the US Naval Observatory Flagstaff Station Parallax Sample
S. K. Leggett, P. Bergeron, John P. Subasavage +18
This paper presents new trigonometric parallaxes and proper motions for 214 stars. The measurements were made at the US Naval Observatory Flagstaff Station (NOFS) between 1989 and…