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arXiv · 1306.6330

The Sloan digital sky survey data release 7 spectroscopic m dwarf catalog iii: The spatial dependence of magnetic activity in the galaxy

J. Sebastian Pineda·Andrew A. West·John J. Bochanski·Adam J. Burgasser
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Abstract

We analyze the magnetic activity of 59,318 M dwarfs from the Sloan Digital Sky Survey (SDSS) Data Release 7. This analysis explores the spatial distribution of M dwarf activity as a function of both vertical distance from the Galactic plane (Z) and planar distance from the Galactic center (R). We confirm the established trends of decreasing magnetic activity (as measured by H-alpha emission) with increasing distance from the mid-plane of the disk and find evidence for a trend in Galactocentric radius. We measure a non-zero radial gradient in the activity fraction in our analysis of stars with spectral types dM3 and dM4. The activity fraction increases with R and can be explained by a decreasing mean stellar age with increasing distance from the Galactic center.

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J. Sebastian Pineda, Andrew A. West, John J. Bochanski, Adam J. Burgasser. 2013-06-26. The Sloan digital sky survey data release 7 spectroscopic m dwarf catalog iii: The spatial dependence of magnetic activity in the galaxy. https://doi.org/10.1088/0004-6256/146/3/50

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