Study of five eccentric eclipsing binary systems

Abstract

In this paper we present the comprehensive analysis of five binary systems: GX Lac, TT Lyr, OGLE LMC-ECL-7641, OGLE LMC-ECL-17660, and OGLE LMC-ECL-17411. With new photometric observations combined with other available data mostly from TESS, MACHO, and OGLE, we calculated new minima timings and study the O - C diagrams. We fitted the light curves and radial velocity curves using PHOEBE software and obtain absolute parameters of these objects. All five binary stars are eccentric. We present the first analysis of TT Lyr, which reveals its nonzero eccentricity. The calculated distance of OGLE LMC-ECL-7641 indicates that this possibly triple system could be located in the Magellanic Stream.