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arXiv · 0711.1861

Characterizing the Near-UV Environment of M Dwarfs

Lucianne M. Walkowicz·Christopher M. Johns-Krull·Suzanne L. Hawley
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Abstract

We report the results of our HST snapshot survey with the ACS HRC PR200L prism, designed to measure the near-UV emission in a sample of nearby M dwarfs. 33 stars were observed, spanning the mass range from 0.1 - 0.6 solar masses (T_eff ~ 2200K - 4000K) where the UV energy distributions vary widely between active and inactive stars. These observations provide much-needed constraints on models of the habitability zone and the atmospheres of possible terrestrial planets orbiting M dwarf hosts, and will be useful in refining the target selection for future space missions such as TPF. We compare our data with a new generation of M dwarf atmospheric models and discuss their implication for the chromospheric energy budget. These NUV data will also be valuable in conjunction with existing optical, FUV and X-ray data to explore unanswered questions regarding the dynamo generation and magnetic heating in low-mass stars.

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Lucianne M. Walkowicz, Christopher M. Johns-Krull, Suzanne L. Hawley. 2008-03-21. Characterizing the Near-UV Environment of M Dwarfs. https://doi.org/10.1086/526421

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