# Spot evolution in the eclipsing binary CoRoT 105895502

## TL;DR

This study analyzes the CoRoT light curve of the eclipsing binary CoRoT 105895502 to investigate starspot behavior, stellar parameters, and surface activity, revealing long-lived and short-lived starspots with potential differential rotation effects.

## Contribution

It provides detailed light-curve modeling and starspot analysis of CoRoT 105895502, highlighting the presence of long-lived and short-lived spots and their possible physical explanations.

## Key findings

- Identified a short-lived (~40 days) starspot stationary in the binary frame.
- Detected a starspot with prograde motion at 2.3 deg/day.
- Starspots contribute up to 0.6% of the quadrature flux.

## 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.