17 papers
Spectroscopic follow-up of compact object binary candidates from Gaia DR3: White dwarfs, neutron stars, black holes, and the parallax zeropoint
Kareem El-Badry, David W. Latham, Hans-Walter Rix +12
Astrometry and radial velocities (RVs) from Gaia DR3 yielded orbits for hundreds of thousands of binary systems, including several samples proposed to contain black holes (BHs), ne…
A Galactic intermediate-mass stripped star with a Wolf-Rayet-like wind
Johanna Müller-Horn, Kareem El-Badry, Andreas A. C. Sander +17
Binary interaction in massive stars is expected to produce a large population of intermediate-mass (- M) envelope-stripped stars, yet such objects have remained elusi…
Searching for the Third Wheel: High-Contrast Imaging Constraints on Tertiaries to Black Hole and Neutron Star Binaries
Pranav Nagarajan, Kareem El-Badry, Aniket Sanghi
The authors performed deep adaptive‑optics near‑infrared imaging of several black‑hole and neutron‑star binaries to look for tertiary companions, finding no convincing detections a…
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…
The Contribution of Disrupted Dense Star Clusters to Gaia's Compact Object Binaries
Aryanna Schiebelbein-Zwack, Claire S. Ye, Marta Reina-Campos +3
We present the first model of the Milky Way's detectable compact object--luminous star binary population from disrupted dense star clusters. We bridge large-scale cosmological star…
Hide and Seek with Gaia. Detectability of Predicted Thin-Disc Metal-Rich RR Lyrae Binaries in Gaia DR3 and DR4
Giuliano Iorio, Pranav Nagarajan, Alexey Bobrick +8
RR Lyrae stars (RRLs) are classical tracers of old stellar populations, yet growing evidence suggests the presence of a metal-rich ([Fe/H]>-0.5), intermediate-age (2-7 Gyr) sub-pop…