# Analysis Of Kepler-71 Activity Through Planetary Transit

## TL;DR

This study analyzes Kepler-71's transit light curves to detect starspots, revealing high stellar activity and providing insights into spot characteristics through modeling planetary transits.

## Contribution

It introduces a method to infer starspot properties from transit data, applied specifically to Kepler-71, demonstrating its high activity level.

## Key findings

- Kepler-71 exhibits high starspot activity with an average of 6 spots per transit.
- Detected starspots have an average size of 0.6 times the planetary radius.
- Starspots show a mean intensity of 0.5 Ic, varying with stellar disk position.

## Abstract

An exoplanet transiting in front of the disk of its parent star may hide a dark starspot causing a detectable change in the light curve, that allows to infer physical characteristics of the spot such as size and intensity. We have analysed the Kepler Space Telescope observations of the star Kepler-71 in order to search for variabilities in 28 transit light curves. Kepler-71 is a star with 0.923Ms and 0.816Rs orbited by the hot Jupiter planet Kepler-71b with radius of 1.0452RJ. The physical parameters of the starspots are determined by fitting the data with a model that simulates planetary transits and enables the inclusion of spots on the stellar surface with different sizes, intensities, and positions. The results show that Kepler-71 is a very active star, with several spot detections, with a mean value of 6 spots per transit with size 0.6Rp and 0.5 Ic, as a function of stellar intensity at disk center (maximum value).