The New Ephemeris and Light Curve Analysis of V870 Ara by the Ground-Based and TESS Data

TL;DR

This study presents new photometric observations and a comprehensive analysis of the contact binary V870 Ara, including updated ephemeris, light curve modeling, and physical parameters derived from combined ground-based and TESS data.

Contribution

It provides the first detailed light curve analysis of V870 Ara using both ground-based and TESS data, and refines its physical and orbital parameters with uncertainty estimates.

Findings

V870 Ara is a contact binary with a very low mass ratio of 0.082.

The system has a high fillout factor of approximately 96%.

The inclination of the binary system is about 73.6 degrees.

Abstract

New CCD photometric observations and their investigation of the W UMa-type binary, V870 Ara, are presented. Light curves of the system were taken through BVI filters from the Congarinni Observatory in Australia. The new ephemeris is calculated based on seven new determined minimum times, together with the TESS data and others compiled from the literature. Photometric solutions determined by the Wilson-Devinney (W-D) code are combined with the Monte Carlo simulation to determine the adjustable parameters' uncertainties. These solutions suggest that V870 Ara is a contact binary system with a mass ratio of 0.082, a fillout factor of 96+-4 percent, and an inclination of 73.60+-0.64 degrees. The absolute parameters of V870 Ara were determined by combining the Gaia EDR3 parallax and photometric elements.