Eclipsing Binary Stars in the OGLE-III Galactic Disk Fields

TL;DR

This paper reports the discovery and analysis of over eleven thousand eclipsing binary stars in the OGLE-III Galactic disk, including new systems, with insights into their period distribution and identification of rare types like quadruples and subdwarfs.

Contribution

The study provides a large, mostly new catalog of eclipsing binaries in the Galactic disk, with detailed period analysis and identification of rare systems, expanding the understanding of binary star populations.

Findings

75% catalog completeness estimate

Maximum orbital period distribution around 0.40 days

Identification of quadruple and subdwarf-B binary candidates

Abstract

We present the analysis of 11 589 eclipsing binary stars identified in twenty-one OGLE-III Galactic disk fields toward constellations of Carina, Centaurus, and Musca. All eclipsing binaries but 402 objects are new discoveries. The binaries have out-of-eclipse brightness between I=12.5 mag and I=21 mag. The completeness of the catalog is estimated at a level of about 75%. Comparison of the orbital period distribution for the OGLE-III disk binaries with systems detected in other recent large-scale Galactic surveys shows the maximum around 0.40 d and an almost flat distribution between 0.5 d and 2.5 d, indepedent of population. Ten doubly eclipsing systems and one eclipsing-ellipsoidal object were found among thousands of variables. Nine of them are candidates for quadruple systems. We also identify ten eclipsing subdwarf-B type binary stars and numerous eclipsing RS CVn type variables. All objects reported in this paper are part of the OGLE-III Catalog of Variable Stars.