THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES

@article{Brown2013THEES,
  title={THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES},
  author={Warren R. Brown and Mukremin Kilic and Carlos Allende Prieto and Alexandros Gianninas and Scott J. Kenyon Sao and Ou and Iac},
  journal={The Astrophysical Journal},
  year={2013},
  volume={769}
}
We present the discovery of 17 low-mass white dwarfs (WDs) in short-period (P ⩽ 1 day) binaries. Our sample includes four objects with remarkable log g ≃ 5 surface gravities and orbital solutions that require them to be double degenerate binaries. All of the lowest surface gravity WDs have metal lines in their spectra implying long gravitational settling times or ongoing accretion. Notably, six of the WDs in our sample have binary merger times <10 Gyr. Four have ≳0.9 M☉ companions. If the… 

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