A hundred new eclipsing binary system candidates studied in a near-infrared window in the VVV survey

TL;DR

This study identifies and characterizes hundreds of new eclipsing binary candidates in the near-infrared VVV survey, providing insights into their physical properties and distribution in the Galactic disc.

Contribution

It presents the first detailed analysis of NIR eclipsing binary candidates in a specific VVV survey tile, including their light curves and physical parameters.

Findings

Detected 100+ new eclipsing binary candidates in the NIR.

Most systems have short periods around 1.22 days.

Contact binaries tend to have shorter periods and low eccentricities.

Abstract

We present the first results obtained from an extensive study of eclipsing binary (EB) system candidates recently detected in the VISTA Variables in the V\'ia L\'actea (VVV) near-infrated (NIR) Survey. We analyze the VVV tile d040 in the southern part of the Galactic disc wherein the interstellar reddening is comparatively low, which makes it possible to detect hundreds of new eclipsing binary candidates. We present here the light curves and the determination of the geometric and physical parameters of the best candidates found in this "NIR window", including 37 contact, 50 detached and 13 semi-detached eclipsing binary systems. We infer that the studied systems have an average of the $K_s$ amplitudes of $0.8$ mag and a median period of 1.22 days where, in general, contact binaries have shorter periods. Using the "Physics Of Eclipsing Binaries" (PHOEBE) interactive interface, which is based on the Wilson and Devinney code, we find that the studied systems have low eccentricities. The studied EBs present mean values of about 5700 K and 4900 K for the $T_1$ and $T_2$ components, respectively. The mean mass-ratio ($q$) for the contact EB stars is $\sim$ 0.44. This new Galactic disc sample is a first approach to the massive study of NIR EB systems.