White dwarf luminosity and mass functions from sloan digital sky survey spectra

We present the first phase in our ongoing work to use Sloan Digital Sky Survey (SDSS) data to create separate white dwarf (WD) luminosity functions (LFs) for two or more different mass ranges. In this paper, we determine the completeness of the SDSS spectroscopic WD sample by comparing a proper-moti...

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Detalles Bibliográficos
Autores: DeGennaro, Steven, Von Hippel, Ted, Winget, D. E., Kepler, S. O., Nitta, Atsuko, Koester, Detlev, Althaus, Leandro Gabriel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2008
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/83461
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/83461
Access Level:acceso abierto
Palabra clave:Ciencias Astronómicas
Stars: luminosity function, mass function
White dwarfs
Descripción
Sumario:We present the first phase in our ongoing work to use Sloan Digital Sky Survey (SDSS) data to create separate white dwarf (WD) luminosity functions (LFs) for two or more different mass ranges. In this paper, we determine the completeness of the SDSS spectroscopic WD sample by comparing a proper-motion selected sample of WDs from SDSS imaging data with a large catalog of spectroscopically determined WDs. We derive a selection probability as a function of a single color (g - i) and apparent magnitude (g) that covers the range -1.0 < g - i < 0.2 and 15 < g < 19.5. We address the observed upturn in log g for WDs with T<SUB>eff</SUB>≲ 12,000 K and offer arguments that the problem is limited to the line profiles and is not present in the continuum. We offer an empirical method of removing the upturn, recovering a reasonable mass function for WDs with T<SUB>eff</SUB>< 12,000 K. Finally, we present a WD LF with nearly an order of magnitude (3358) more spectroscopically confirmed WDs than any previous work.