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arXiv · 1610.02441

Constraining the Variability and Binary Fraction of Galactic Center Young Stars

Abhimat K. Gautam·Tuan Do·Andrea M. Ghez·Jessica R. Lu·Mark R. Morris·Shoko Sakai·Gunther Witzel·Breann N. Sitarski·Samantha Chappell
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Abstract

We present constraints on the variability and binarity of young stars in the central 10 arcseconds (~0.4 pc) of the Milky Way Galactic Center (GC) using Keck Adaptive Optics data over a 12 year baseline. Given our experiment's photometric uncertainties, at least 36% of our sample's known early-type stars are variable. We identified eclipsing binary systems by searching for periodic variability. In our sample of spectroscopically confirmed and likely early-type stars, we detected the two previously discovered GC eclipsing binary systems. We derived the likely binary fraction of main sequence, early-type stars at the GC via Monte Carlo simulations of eclipsing binary systems, and find that it is at least 32% with 90% confidence.

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Abhimat K. Gautam, Tuan Do, Andrea M. Ghez, Jessica R. Lu, Mark R. Morris, Shoko Sakai, Gunther Witzel, Breann N. Sitarski, Samantha Chappell. 2016-10-07. Constraining the Variability and Binary Fraction of Galactic Center Young Stars. https://doi.org/10.1017/s1743921316011996

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