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arXiv · 1004.4002

The Luminosity and Mass Functions of Low-Mass Stars in the Galactic Disk: II. The Field

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

We report on new measurements of the luminosity function (LF) and mass function (MF) of field low-mass dwarfs derived from Sloan Digital Sky Survey (SDSS) Data Release 6 (DR6) photometry. The analysis incorporates ~15 million low-mass stars (0.1 Msun < M < 0.8 Msun), spread over 8,400 square degrees. Stellar distances are estimated using new photometric parallax relations, constructed from ugriz photometry of nearby low-mass stars with trigonometric parallaxes. We use a technique that simultaneously measures Galactic structure and the stellar LF from 7 < M_r < 16. We compare the LF to previous studies and convert to a MF using the mass-luminosity relations of Delfosse et al., 2000. The system MF, measured over -1.0 < log M/Msun < -0.1, is well-described by a log-normal distribution with Mo = 0.25 Msun. We stress that our results should not be extrapolated to other mass regimes. Our work generally agrees with prior low-mass stellar MFs and places strong constraints on future star-formation studies of the Milky Way.

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John J. Bochanski, Suzanne L. Hawley, Kevin R. Covey, Andrew A. West, I. Neill Reid, David A. Golimowski, Zeljko Ivezic. 2010-04-22. The Luminosity and Mass Functions of Low-Mass Stars in the Galactic Disk: II. The Field. https://doi.org/10.1088/0004-6256%2F139%2F6%2F2679

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