Atmospheric Mass Loss of Extrasolar Planets Orbiting Magnetically Active
MNRAS 000, 1–?? (2017) Preprint 8 August 2018 Compiled using MNRAS LATEX style file v3.0 Atmospheric mass loss of extrasolar planets orbiting magnetically active host stars Lalitha Sairam,1⋆ J. H. M. M. Schmitt,2 and Spandan Dash3 1Indian Institute of Astrophysics, II Block, Koramangala, Bangalore 560 034, India 2Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg 3Indian Institute of Science, C.V Raman Avenue, Yeshwantpur, Bangalore 560 012, India Accepted XXX. Received YYY; in original form ZZZ ABSTRACT Magnetic stellar activity of exoplanet hosts can lead to the production of large amounts of high-energy emission, which irradiates extrasolar planets, located in the immediate vicinity of such stars. This radiation is absorbed in the planets’ upper atmospheres, which consequently heat up and evaporate, possibly leading to an irradiation-induced mass-loss. We present a study of the high-energy emission in the four magnetically ac- tive planet-bearing host stars Kepler-63, Kepler-210, WASP-19, and HAT-P-11, based on new XMM-Newton observations. We find that the X-ray luminosities of these stars are rather high with orders of magnitude above the level of the active Sun. The total XUV irradiation of these planets is expected to be stronger than that of well stud- ied hot Jupiters. Using the estimated XUV luminosities as the energy input to the planetary atmospheres, we obtain upper limits for the total mass loss in these hot Jupiters. Key words: stars: activity – stars: coronae – stars: low-mass, late-type, planetary systems – stars: individual: Kepler-63, Kepler-210, WASP-19, HAT-P-11 1 INTRODUCTION through Jeans escape, the observations of atmospheric mass loss in HD 209458 b (Vidal-Madjar et al.
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