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arXiv · 0810.2343

Our Nearest 15 Million Neighbors: The Field Low-Mass Stellar Luminosity and Mass Functions

John J. Bochanski·Suzanne L. Hawley·I. Neill Reid·Kevin R. Covey·Andrew A. West·David A. Golimowski·Zeljko Ivezic
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Abstract

We report on a new measurement of the luminosity function (LF) and mass function (MF) of field low-mass dwarfs using Sloan Digital Sky Survey (SDSS) photometry. The final catalog is composed of ~15 million low-mass stars (0.1 Msun < M < 0.8 Msun), spread over 8,400 square degrees. Distances to the stars are estimated using new photometric parallax relations, constructed from ugriz photometry of nearby low-mass stars with trigonometric parallaxes. The LF is measured with a novel technique, which simultaneously measures Galactic structure and the stellar LF. The resulting LF is compared to previous studies and converted to a MF. The MF is well-described by a log-normal distribution, with Mo = 0.27 Msun.

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John J. Bochanski, Suzanne L. Hawley, I. Neill Reid, Kevin R. Covey, Andrew A. West, David A. Golimowski, Zeljko Ivezic. 2008-10-14. Our Nearest 15 Million Neighbors: The Field Low-Mass Stellar Luminosity and Mass Functions. https://doi.org/10.1063/1.3099284

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