THE LUMINOSITY AND MASS FUNCTIONS OF LOW-MASS STARS IN THE GALACTIC DISK. II. THE FIELD

Journal Article · Tue Jun 15 04:00:00 EDT 2010 · Astronomical Journal (New York, N.Y. Online)

DOI:https://doi.org/10.1088/0004-6256/139/6/2679· OSTI ID:21443060

Bochanski, John J; Hawley, Suzanne L; Ivezic, Zeljko ^[1]; Covey, Kevin R ^[2]; West, Andrew A ^[3]; Reid, I Neill

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1. Astronomy Department, University of Washington, P.O. Box 351580, Seattle, WA 98195 (United States)
2. Department of Astronomy, Cornell University, 226 Space Sciences Building, Ithaca, NY 14853 (United States)
3. Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Building 37, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)

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 Data Release 6 photometry. The analysis incorporates {approx}15 million low-mass stars (0.1 M{sub sun}< M < 0.8 M{sub sun}), spread over 8400 deg{sup 2}. 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{sub r} < 16. We compare the LF to previous studies and convert to an MF using the mass-luminosity relations of Delfosse et al. The system MF, measured over -1.0< log M/M{sub sun} <-0.1, is well described by a lognormal distribution with M{sub o} = 0.25 M{sub sun}. 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 theoretical star formation studies.

• OSTI ID: 21443060
• Journal Information: Astronomical Journal (New York, N.Y. Online), Journal Name: Astronomical Journal (New York, N.Y. Online) Journal Issue: 6 Vol. 139; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
DISTANCE
DISTRIBUTION
DWARF STARS
FUNCTIONS
GALAXIES
LUMINOSITY
MASS
OPTICAL PROPERTIES
PHOTOMETRY
PHYSICAL PROPERTIES
SPATIAL DISTRIBUTION
STARS