Spotted eclipsing binary KIC 7023917 with δ-Scuti pulsations

Abstract

Eclipsing binary KIC 7023917 is one of nearly three thousand other binaries in the well-known Kepler Eclipsing Binary Catalog. However, it has some uncommon features. We focused on this system because we detected fast anti-correlated changes on the O-C diagram which could suggest the presence of apsidal motion. However, these changes are very fast for apsidal motion and the orbit of this binary is circular. Detailed analysis of the Kepler and TESS light curves reveals deformation of the light curve by short-periodic pulsations and the O'Connell effect caused by stellar spot(s). Here, we present our initial study of this system and a possible explanation of the observed O-C diagram.