• DOI:10.1086/514327
• Corpus ID: 18587748

The Lowest Mass White Dwarf

@article{Kilic2007TheLM,
  title={The Lowest Mass White Dwarf},
  author={Mukremin Kilic and Carlos Allende Prieto and Warren R. Brown and Detlev Koester},
  journal={The Astrophysical Journal},
  year={2007},
  volume={660},
  pages={1451 - 1461}
}

• M. Kilic, C. Prieto, +1 author D. Koester
• Published 15 November 2006
• Physics, Geology
• The Astrophysical Journal

Extremely low mass white dwarfs are very rare objects likely formed in compact binary systems. We present MMT optical spectroscopy of 42 low-mass white dwarf candidates serendipitously discovered in a survey for hypervelocity B-type stars. One of these objects, SDSS J0917+46, has Teff = 11,288 ± 72 K and log g = 5.48 ± 0.03; with an estimated mass of 0.17 M☉, it is the lowest gravity/mass white dwarf currently known. However, 40 of the low-mass candidates are normal DA white dwarfs with apparently inaccurate SDSS g magnitudes. We revisit the identification of low-mass white dwarf candidates previously found in the SDSS and conclude that four objects have M < 0.2 M☉. None of these white dwarfs show excess emission from a binary companion, and radial velocity searches will be necessary to constrain the nature of the unseen companions.