9 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…
Population demographics of post-interaction WDMS binaries: From common envelope evolution to stable mass transfer
Natsuko Yamaguchi, Kareem El-Badry, Cheyanne Shariat
The authors jointly model three observational samples of white‑dwarf + main‑sequence binaries to constrain how mass transfer and common‑envelope phases shape their demographics, fi…
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…
Ongoing and Post-Mass-Transfer Binaries: A Living Catalog and Unified Review of Binary Mass Transfer Products
Lieke A. C. van Son, Natsuko Yamaguchi, Pranav Nagarajan +6
Mass transfer is arguably the most defining interaction in binary stellar systems, yet many aspects of its physics remain poorly understood, from stability to endpoints and observa…
Thermally inflated accretors in post-mass transfer binaries: Abell 35 and its class revisited
Soumyadeep Bhattacharjee, Kareem El-Badry, Jim Fuller +2
A small but growing class of binaries containing hot () white dwarfs (WDs) and rapidly rotating, apparently subgiant companions -- including the proto…
Chemical Signatures of AGB Mass Transfer in Gaia White Dwarf Companions
Natsuko Yamaguchi, Kareem El-Badry, Henrique Reggiani +2
We present a homogeneous abundance analysis of 160 main-sequence stars in astrometric white-dwarf + main-sequence (WD+MS) binaries with orbits from Gaia DR3. These systems have AU-…