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The White Dwarf Luminosity Function from SDSS Imaging Data

Hugh C. Harris·Jeffrey A. Munn·Mukremin Kilic·James Liebert·Kurtis A. Williams·Ted von Hippel·Stephen E. Levine·David G. Monet·Daniel J. Eisenstein·S. J. Kleinman·T. S. Metcalfe·Atsuko Nitta·D. E. Winget·J. Brinkmann·Masataka Fukugita·G. R. Knapp·Robert H. Lupton·J. Allyn Smith·Donald P. Schneider
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Abstract

A sample of white dwarfs is selected from SDSS DR3 imaging data using their reduced proper motions, based on improved proper motions from SDSS plus USNO-B combined data. Numerous SDSS and followup spectra (Kilic et al. 2005) are used to quantify completeness and contamination of the sample; kinematic models are used to understand and correct for velocity-dependent selection biases. A luminosity function is constructed covering the range 7 < M_bol < 16, and its sensitivity to various assumptions and selection limits is discussed. The white dwarf luminosity function based on 6000 stars is remarkably smooth, and rises nearly monotonically to M_bol = 15.3. It then drops abruptly, although the small number of low-luminosity stars in the sample and their unknown atmospheric composition prevent quantitative conclusions about this decline. Stars are identified that may have high tangential velocities, and a preliminary luminosity function is constructed for them.

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Hugh C. Harris, Jeffrey A. Munn, Mukremin Kilic, James Liebert, Kurtis A. Williams, Ted von Hippel, Stephen E. Levine, David G. Monet, Daniel J. Eisenstein, S. J. Kleinman, T. S. Metcalfe, Atsuko Nitta, D. E. Winget, J. Brinkmann, Masataka Fukugita, G. R. Knapp, Robert H. Lupton, J. Allyn Smith, Donald P. Schneider. 2005-10-29. The White Dwarf Luminosity Function from SDSS Imaging Data. https://doi.org/10.1086/497966

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