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Description
We have conducted a detailed new survey of the local population of white dwarfs lying within 20pc of the Sun. A new revised catalog of local white dwarfs containing 122 entries (126 individual degenerate stars) is presented. This list contains 27 white dwarfs not included in a previous list from 2002, as well as new and recently published trigonometric parallaxes. In several cases new members of the local white dwarf population have come to light through accurate photometric distance estimates. In addition, a suspected new double degenerate system (WD 0423+120) has been identified. The 20pc sample is currently estimated to be 80% complete. Using a variety of recent spectroscopic, photometric, and trigonometric distance determinations, we re-compute a space density of 4.8+/-0.5x10^-3^pc^-3^ corresponding to a mass density of 3.2+/-0.3x10^-3^M_{sun}_pc^-3^ from the complete portion of the sample within 13pc. We find an overall mean mass for the local white dwarfs of 0.665M_{sun}_, a value larger than most other non-volume-limited estimates. Although the sample is small, we find no evidence of a correlation between mass and temperature in which white dwarfs below 13000K are systematically more massive than those above this temperature. Within 20pc 25% of the white dwarfs are in binary systems (including double degenerate systems). Approximately 6% are double degenerates and 6.5% are Sirius-like systems. The fraction of magnetic white dwarfs in the local population is found to be 13%.
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