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arXiv · 1509.03645

A Catalog of GALEX Ultraviolet Emission from Spectroscopically Confirmed M Dwarfs

David O. Jones·Andrew A. West
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Abstract

We present a catalog of GALEX Near-UV (NUV) and Far-UV (FUV) photometry for the Palomar/MSU and SDSS DR7 spectroscopic M dwarf catalogs. The catalog contains NUV measurements matched to 577 spectroscopically confirmed M dwarfs and FUV measurements matched to 150 spectroscopically confirmed M dwarfs. Using these data, we find that NUV and FUV luminosities strongly correlate with Hα emission, a typical indicator of magnetic activity in M dwarfs. We also examine the fraction of M dwarfs with varying degrees of strong line emission at NUV wavelengths. Our results indicate that the frequency of M dwarf NUV emission peaks at intermediate spectral types, with at least ~30% of young M4-M5 dwarfs having some level of activity. For mid-type M dwarfs, we show that NUV emission decreases with distance from the Galactic plane, a proxy for stellar age. Our complete matched source catalog is available online.

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David O. Jones, Andrew A. West. 2015-09-11. A Catalog of GALEX Ultraviolet Emission from Spectroscopically Confirmed M Dwarfs. https://doi.org/10.3847/0004-637x%2F817%2F1%2F1

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