Spot evolution in the eclipsing binary CoRoT 105895502

Abstract

Stellar activity is ubiquitous in late-type stars. The special geometry of eclipsing binary systems is particularly advantageous to study the stellar surfaces and activity. We present a detailed study of the 145 d CoRoT light curve of the short-period eclipsing binary CoRoT 105895502. By means of light-curve modeling with Nightfall, we determine the orbital period, effective temperature, Roche-lobe filling factors, mass ratio, and orbital inclination of CoRoT 105895502 and analyze the temporal behavior of starspots in the system. Our analysis shows one comparably short-lived (about 40 d) starspot, remaining quasi-stationary in the binary frame, and one starspot showing prograde motion at a rate of 2.3 deg per day, whose lifetime exceeds the duration of the observation. In the CoRoT band, starspots account for as much as 0.6 % of the quadrature flux of CoRoT 105895502, however we cannot attribute the spots to individual binary components with certainty. Our findings can be explained by differential rotation, asynchronous stellar rotation, or systematic spot evolution.

Accepted in A&A

References in corpus (9)

• The Gaia mission
• Observational Evidence for Tidal Interaction in Close Binary Systems
• An Observational Study of Tidal Synchronization in Solar-Type Binary Stars in the Open Clusters M35 and M34
• Tracking the Stellar Longitudes of Starspots in Short-Period Kepler Binaries
• Stellar loci II. a model-free estimate of the binary fraction for field FGK stars
• Starspot signature on the light curve: Learning about the latitudinal distribution of spots
• Recurrent starspot activity and differential rotation in KIC 11560447
• Rotation--differential rotation relationships for late-type single and binary stars from Doppler imaging
• Characterization of CoRoT target fields with BEST: Identification of periodic variable stars in the LRa1 field