Constraining the Variability and Binary Fraction of Galactic Center Young Stars

TL;DR

This study uses 12 years of Keck Adaptive Optics data to constrain the variability and binary fraction of young stars in the Galactic Center, revealing at least 36% variability and a binary fraction of at least 32%.

Contribution

It provides the first robust estimate of the binary fraction of young stars in the Galactic Center using long-term observational data.

Findings

At least 36% of young stars are variable.

Detected two known eclipsing binary systems.

Binary fraction estimated to be at least 32% with 90% confidence.

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.