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arXiv · 1511.05306

The Host Stars of Keplers Habitable Exoplanets: Superflares, Rotation and Activity

D. J. Armstrong·C. E. Pugh·A. -M. Broomhall·D. J. A. Brown·M. N. Lund·H. P. Osborn·D. L. Pollacco
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Abstract

We embark on a detailed study of the lightcurves of Keplers most Earth-like exoplanet host stars using the full length of Kepler data. We derive rotation periods, photometric activity indices, flaring energies, mass loss rates, gyrochronological ages, X-ray luminosities and consider implications for the planetary magnetospheres and habitability. Furthermore, we present the detection of superflares in the lightcurve of Kepler-438, the exoplanet with the highest Earth Similarity Index to date. Kepler-438b orbits at a distance of 0.166AU to its host star, and hence may be susceptible to atmospheric stripping. Our sample is taken from the Habitable Exoplanet Catalogue, and consists of the stars Kepler-22, Kepler-61, Kepler-62, Kepler-174, Kepler-186, Kepler-283, Kepler-296, Kepler-298, Kepler-438, Kepler-440, Kepler-442, Kepler-443 and KOI-4427, between them hosting 15 of the most habitable transiting planets known to date from Kepler.

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D. J. Armstrong, C. E. Pugh, A. -M. Broomhall, D. J. A. Brown, M. N. Lund, H. P. Osborn, D. L. Pollacco. 2015-11-17. The Host Stars of Keplers Habitable Exoplanets: Superflares, Rotation and Activity. https://doi.org/10.1093/mnras%2Fstv2419

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