203 citations · 771 across the 30 of their papers we have counts for
31 papers
A survey of ultra-compact high-state AM CVn binaries with ZTF and Gaia: New discoveries and observational constraints on Galactic space density
Ilkham Galiullin, Antonio C. Rodriguez, Kareem El-Badry +9
Ultra-compact AM CVn binaries in the high-state of stable mass transfer () are expected to be among the loudest persistent sources for upcomin…
V407 Vul: a triple star system with an AM CVn detectable by gravitational wave observatories
James Munday, Antonio C. Rodriguez, Nicole Reindl +23
The AM CVn class includes mass transferring, ultra-compact double white dwarf binaries with orbital periods on the timescale of minutes. A long-standing puzzle is that none of the…
A systematic survey for hypervelocity runaways from thermonuclear supernovae
Kareem El-Badry, Klaus Werner, Ken J. Shen +16
The explosion of a white dwarf (WD) in a close binary can launch a surviving runaway star at velocities of . Such runaways provide a direct probe of…
A half-ring of ionized circumstellar material trapped in the magnetosphere of a white dwarf merger remnant
Andrei A. Cristea, Ilaria Caiazzo, Tim Cunningham +31
Many white dwarfs are observed in compact double white dwarf binaries and, through the emission of gravitational waves, a large fraction are destined to merge. The merger remnants…
Discovery of two new polars evolved past the period bounce
Tim Cunningham, Ilaria Caiazzo, Gracjan Sienkiewicz +13
We report the discovery of two new magnetic cataclysmic variables with brown dwarf companions and long orbital periods ( and min). This discovery incr…
A ZTF Search for Circumstellar Debris Transits in White Dwarfs: Six New Candidates, one with Gas Disk Emission, identified in a Novel Metric Space
Soumyadeep Bhattacharjee, Zachary P. Vanderbosch, Mark A. Hollands +13
White dwarfs (WDs) showing transits from orbiting planetary debris provide significant insights into the structure and dynamics of debris disks. This is a rare class of objects wit…
Sporadic Dips from Extended Debris Transiting the Metal-Rich White Dwarf SBSS 1232+563
J. J. Hermes, Joseph A. Guidry, Zachary P. Vanderbosch +5
We present the discovery of deep but sporadic transits in the flux of SBSS 1232+563, a metal-rich white dwarf polluted by disrupted exoplanetary debris. Nearly 25 years of photomet…
A Link Between White Dwarf Pulsars and Polars: Multiwavelength Observations of the 9.36-Minute Period Variable Gaia22ayj
Antonio C. Rodriguez, Kareem El-Badry, Pasi Hakala +30
White dwarfs (WDs) are the most abundant compact objects, and recent surveys have suggested that over a third of WDs in accreting binaries host a strong (B 1 MG) magnetic…
Black hole jets on the scale of the Cosmic Web
Martijn S. S. L. Oei, Martin J. Hardcastle, Roland Timmerman +10
Jets launched by supermassive black holes transport relativistic leptons, magnetic fields, and atomic nuclei from the centres of galaxies to their outskirts and beyond. These outfl…
Variability of Central Stars of Planetary Nebulae with the Zwicky Transient Facility. I. Methods, Short-Timescale Variables, Binary Candidates, and the Unusual Nucleus of WeSb 1
Soumyadeep Bhattacharjee, S. R. Kulkarni, Albert K. H. Kong +16
Over the past several decades, time-series photometry of CSPNe has yielded significant results including, but not limited to, discoveries of nearly 100 binary systems, insights int…
Cataclysmic Variables and AM CVn Binaries in SRG/eROSITA + Gaia: Volume Limited Samples, X-ray Luminosity Functions, and Space Densities
Antonio C. Rodriguez, Kareem El-Badry, Valery Suleimanov +22
We present volume-limited samples of cataclysmic variables (CVs) and AM CVn binaries jointly selected from SRG/eROSITA eRASS1 and \textit{Gaia} DR3 using an X-ray + optical color-c…
The companion mass distribution of post common envelope hot subdwarf binaries: evidence for boosted and disrupted magnetic braking?
Lisa Blomberg, Kareem El-Badry, Katelyn Breivik +6
We measure the mass distribution of main-sequence (MS) companions to hot subdwarf B stars (sdBs) in post-common envelope binaries (PCEBs). We carried out a spectroscopic survey of…
Searching for New Cataclysmic Variables in the Chandra Source Catalog
Ilkham Galiullin, Antonio C. Rodriguez, Kareem El-Badry +14
Cataclysmic variables (CVs) are compact binary systems in which a white dwarf accretes matter from a Roche-lobe-filling companion star. In this study, we searched for new CVs in th…
A Joint SRG/eROSITA + ZTF Search: Discovery of a 97-min Period Eclipsing Cataclysmic Variable with Evidence of a Brown Dwarf Secondary
Ilkham Galiullin, Antonio C. Rodriguez, Shrinivas R. Kulkarni +24
Cataclysmic variables (CVs) that have evolved past the period minimum during their lifetimes are predicted to be systems with a brown dwarf donor. While population synthesis models…
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 …
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…
A rotating white dwarf shows different compositions on its opposite faces
Ilaria Caiazzo, Kevin B. Burdge, Pier-Emmanuel Tremblay +35
White dwarfs, the extremely dense remnants left behind by most stars after their death, are characterised by a mass comparable to that of the Sun compressed into the size of an Ear…
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…
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…
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 (…
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…
A very luminous jet from the disruption of a star by a massive black hole
Igor Andreoni, Michael W. Coughlin, Daniel A. Perley +78
Tidal disruption events (TDEs) are bursts of electromagnetic energy released when supermassive black holes (SMBHs) at the centers of galaxies violently disrupt a star that passes t…