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LP 400-22, A very low-mass and high-velocity white dwarf

Adela Kawka·Stephane Vennes·Terry D. Oswalt·J. Allyn Smith·Nicole M. Silvestri
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Abstract

We report the identification of LP 400-22 (WD 2234+222) as a very low-mass and high-velocity white dwarf. The ultraviolet GALEX and optical photometric colors and a spectral line analysis of LP 400-22 show this star to have an effective temperature of 11080+/-140 K and a surface gravity of log g = 6.32+/-0.08. Therefore, this is a helium core white dwarf with a mass of 0.17 M_solar. The tangential velocity of this white dwarf is 414+/-43 km/s, making it one of the fastest moving white dwarfs known. We discuss probable evolutionary scenarios for this remarkable object.

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Adela Kawka, Stephane Vennes, Terry D. Oswalt, J. Allyn Smith, Nicole M. Silvestri. 2006-05-05. LP 400-22, A very low-mass and high-velocity white dwarf. https://doi.org/10.1086/505143

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