18 citations · 44 across the 21 of their papers we have counts for
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Calibration of the Next Generation Palomar Spectrograph as a Stellar Speedometer
Pranav Nagarajan, Kareem El-Badry
We calibrate the Next Generation Palomar Spectrograph (NGPS) for precision stellar radial-velocity (RV) measurements using repeated observations of 24 Gaia-ESO RV standards spannin…
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…
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…
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…
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
Black holes (BHs) and neutron stars (NSs) with low-mass stellar companions challenge traditional isolated binary evolution models, motivating hierarchical triple evolution as a pro…
Deep Adaptive Optics Imaging Rules Out a Helium Star Companion to PSR J1928+1815
Pranav Nagarajan, Kareem El-Badry, Jim Fuller +2
PSR J1928+1815 is a 10.55 ms millisecond pulsar in a 3.6 hr orbit with a massive (-) companion that produces extended radio eclipses. The companion, proposed t…
Pegasi Ascendant: Ranking Constellation Genitives on their Aesthetic Merit
Pranav Nagarajan
Despite their ubiquity in the astronomical literature, there is no consensus tier list of the genitive forms of the 88 constellations officially recognized by the International Ast…
The KPF-SLOPE Survey - Small, Compact Multi-Planet Systems Appear Spin-Orbit Aligned
Luke B. Handley, Andrew W. Howard, Fei Dai +16
The angle between stellar spin axes and planetary orbits -- stellar obliquity -- probes the dynamics of planetary migration and evolution. The obliquities of giant planets have bee…
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…
Testing models for fully and partially stripped low-mass stars with Gaia: Implications for hot subdwarfs, binary RR Lyrae, and black hole impostors
Pranav Nagarajan, Kareem El-Badry, Alexey Bobrick +4
When low-mass ( ) red giants lose their envelopes to a companion just before the helium flash, the resulting mass transfer can produce binaries hosting hot s…
BE Lyncis is not a Black Hole Binary: Lessons From Gaia and Hipparcos Astrometry
Pranav Nagarajan, Kareem El-Badry, Thomas J. Maccarone +3
BE Lyncis (BE Lyn) is a well-studied high-amplitude Scuti variable star (HADS). Recently, Niu et al. (2026) analyzed a 39-year baseline of times of maximum light of BE Lyn, rep…