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.
@article{arxiv.0711.1861,
title = {Characterizing the Near-UV Environment of M Dwarfs},
author = {Lucianne M. Walkowicz and Christopher M. Johns-Krull and Suzanne L. Hawley},
journal= {arXiv preprint arXiv:0711.1861},
year = {2009}
}
Comments
21 pages, 17 figures; accepted for publication in ApJ - correction of unit label in Table 2