8 papers
Spin-Orbit Alignment of Two Neptune-size Planets Younger than 500 Myr: TOI-560 b and TOI-5082 b
Elina Y. Zhang, Fei Dai, Andrew W. Howard +25
Stellar obliquity measurements provide a direct probe of planetary system dynamics, but remain sparse for Neptune-size planets, particularly at young ages. We present Rossiter-McLa…
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…
Lithium as a Signpost for Compact Object Binary Candidates in the LAMOST Medium Resolution Survey
Yang Shen, Joshua D. Simon, Kareem El-Badry +1
Binary systems with black hole or neutron star companions are often associated with lithium enhancement. Gaia NS1, a recently discovered neutron-star binary with a lithium-enhanced…
Radial Velocity Orbital Solutions for Candidate Black Hole and Neutron Star Binary Systems in the Gaia Data Release 3 Catalog
Joshua D. Simon, Casey Y. Lam, Kareem El-Badry +8
We present spectroscopic followup observations of binary systems from the Gaia Data Release 3 (DR3) binary catalog that were selected to have large enough mass functions for their…
A search for black holes with metal-poor stellar companions: I. Survey sample selection and single epoch radial velocity follow-up
Casey Y. Lam, Joshua D. Simon, Kareem El-Badry +3
Stellar-mass black holes (BHs) above are predicted to form from low-metallicity progenitors, but direct detections of such systems in the Milky Way remain scarce. Moti…
A Spectroscopic Search for Dormant Black Holes in Low-Metallicity Binaries
Pranav Nagarajan, Kareem El-Badry, Henrique Reggiani +9
The discovery of the massive black hole (BH) system Gaia BH3 in pre-release Gaia DR4 data suggests that wide BH binaries with luminous companions may be significantly overrepresent…