454 citations · 7.2k across the 161 of their papers we have counts for
21 papers · 1 filter
The photospheres of the hottest fastest stars in the Galaxy
Klaus Werner, Nicole Reindl, Thomas Rauch +2
We perform nonlocal thermodynamic equilibrium (NLTE) model atmosphere analyses of the three hottest hypervelocity stars (space velocities between 1500-2800 km s) k…
No X-Rays or Radio from the Nearest Black Holes and Implications for Future Searches
Antonio C. Rodriguez, Yvette Cendes, Kareem El-Badry +1
Astrometry from the Gaia mission was recently used to discover the two nearest known stellar-mass black holes (BHs), Gaia BH1 and Gaia BH2. Both systems contain …
Evidence for saturated and disrupted magnetic braking from samples of detached close binaries with M and K dwarfs
Diogo Belloni, Matthias R. Schreiber, Maxwell Moe +2
Context. Recent observations of close detached eclipsing M and K dwarf binaries have provided substantial support for magnetic saturation when stars rotate sufficiently fast, leadi…
Measuring The Mass-Radius Relation of White Dwarfs Using Wide Binaries
Stefan Arseneau, Vedant Chandra, Hsiang-Chih Hwang +10
Measuring the mass-radius relation of individual white dwarfs is an empirically challenging task that has been performed for only a few dozen stars. We measure the white dwarf mass…
An Extremely Massive White Dwarf Escaped From the Hyades Star Cluster
David R. Miller, Ilaria Caiazzo, Jeremy Heyl +5
We searched the Gaia DR3 database for ultramassive white dwarfs with kinematics consistent with having escaped the nearby Hyades open cluster, identifying three such candidates. Tw…
Discovery of a Proto-White Dwarf with a Massive Unseen Companion
Gautham Adamane Pallathadka, Vedant Chandra, Nadia L. Zakamska +8
We report the discovery of SDSS~J022932.28+713002.7, a nascent extremely low-mass (ELM) white dwarf (WD) orbiting a massive ( at 2 confidence) companion with a per…
Wide post-common envelope binaries containing ultramassive white dwarfs: evidence for efficient envelope ejection in massive AGB stars
Natsuko Yamaguchi, Kareem El-Badry, Jim Fuller +7
Post-common-envelope binaries (PCEBs) containing a white dwarf (WD) and a main-sequence (MS) star can constrain the physics of common envelope evolution and calibrate binary evolut…
Triage of the Gaia DR3 astrometric orbits. II. A census of white dwarfs
S. Shahaf, N. Hallakoun, T. Mazeh +4
The third data release of Gaia was the first to include orbital solutions assuming non-single stars. Here, we apply the astrometric triage technique of Shahaf et al. to identify bi…
Gaia22dkvLb: A Microlensing Planet Potentially Accessible to Radial-Velocity Characterization
Zexuan Wu, Subo Dong, Tuan Yi +50
We report discovering an exoplanet from following up a microlensing event alerted by Gaia. The event Gaia22dkv is toward a disk source rather than the traditional bulge microlensin…
The fastest stars in the Galaxy
Kareem El-Badry, Ken J. Shen, Vedant Chandra +18
We report a spectroscopic search for hypervelocity white dwarfs (WDs) that are runaways from Type Ia supernovae (SNe Ia) and related thermonuclear explosions. Candidates are select…
A transiting brown dwarf in a 2 hour orbit
Kareem El-Badry, Kevin B. Burdge, Jan van Roestel +1
We report the discovery of ZTF J2020+5033, a high-mass brown dwarf (BD) transiting a low-mass star with an orbital period of 1.90 hours. Phase-resolved spectroscopy, optical and in…
Roman CCS White Paper: Characterizing the Galactic population of isolated black holes
Casey Y. Lam, Natasha Abrams, Jeff Andrews +34
Although there are estimated to be 100 million isolated black holes (BHs) in the Milky Way, only one has been found so far, resulting in significant uncertainty about their propert…
SRGeJ045359.9+622444: A 55-min Period Eclipsing AM CVn Discovered from a Joint SRG/eROSITA + ZTF Search
Antonio C. Rodriguez, Ilkham Galiullin, Marat Gilfanov +24
AM CVn systems are ultra-compact binaries where a white dwarf accretes from a helium-rich degenerate or semi-degenerate donor. Some AM CVn systems will be among the loudest sources…
The Galactic Center with Roman
Sean K. Terry, Matthew W. Hosek, Jessica R. Lu +31
We advocate for a Galactic center (GC) field to be added to the Galactic Bulge Time Domain Survey (GBTDS). The new field would yield high-cadence photometric and astrometric measur…
NANCY: Next-generation All-sky Near-infrared Community surveY
Jiwon Jesse Han, Arjun Dey, Adrian M. Price-Whelan +206
The Nancy Grace Roman Space Telescope is capable of delivering an unprecedented all-sky, high-spatial resolution, multi-epoch infrared map to the astronomical community. This oppor…
Constraints on the cosmological coupling of black holes from Gaia
Rene Andrae, Kareem El-Badry
Recent work has suggested that black holes (BHs) could be cosmologically coupled to the accelerated expansion of the universe, potentially becoming a candidate for dark energy. Thi…
Sodium enhancement in evolved cataclysmic variables
Natsuko Yamaguchi, Kareem El-Badry, Antonio C. Rodriguez +3
We present follow-up spectroscopy of 21 cataclysmic variables (CVs) with evolved secondaries and ongoing or recently-terminated mass transfer. Evolutionary models predict that the…
Spectroscopic follow-up of black hole and neutron star candidates in ellipsoidal variables from Gaia DR3
Pranav Nagarajan, Kareem El-Badry, Antonio C. Rodriguez +2
We present multi-epoch spectroscopic follow-up of a sample of ellipsoidal variables selected from Gaia DR3 as candidates for hosting quiescent black holes (BHs) and neutron stars (…
Orbital decay in an accreting and eclipsing 13.7 minute orbital period binary with a luminous donor
Kevin B. Burdge, Kareem El-Badry, Saul Rappaport +24
We report the discovery of ZTF J0127+5258, a compact mass-transferring binary with an orbital period of 13.7 minutes. The system contains a white dwarf accretor, which likely origi…
A red giant orbiting a black hole
Kareem El-Badry, Hans-Walter Rix, Yvette Cendes +18
We report spectroscopic and photometric follow-up of a dormant black hole (BH) candidate from Gaia DR3. The system, which we call Gaia BH2, contains a red giant a…
What Causes The Formation of Disks and End of Bursty Star Formation?
Philip F. Hopkins, Alexander B. Gurvich, Xuejian Shen +17
As they grow, galaxies can transition from irregular/spheroidal with 'bursty' star formation histories (SFHs), to disky with smooth SFHs. But even in simulations, the direct physic…