A Helium White Dwarf of Extremely Low Mass

  title={A Helium White Dwarf of Extremely Low Mass},
  author={James William Liebert and Pierre Bergeron and Daniel J. Eisenstein and Hugh C. Harris and Scott J. Kleinman and Atsuko Nitta and Jurek Krzesinski},
  journal={The Astrophysical Journal Letters},
  pages={L147 - L149}
We analyze the spectrum of an unusually low mass white dwarf, SDSS J123410.37-022802.9 (0335-264-52000), found in our recent, white dwarf catalog from the first data release (DR1) of the Sloan Digital Sky Survey (SDSS). Two independent, model atmosphere fits result in an accurate determination of atmospheric and stellar parameters. The more hands-on analysis yields Teff = 17,470 ± 750 K and log g = 6.38 ± 0.05. We argue that the object cannot be a main-sequence A star, a horizontal-branch star… 
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This book introduces the theory of the internal structure of stars and their evolution in time. It presents the basic physics of stellar interiors, methods for solving the underlying equations, and