Direct Distance Measurement to the Dusty White Dwarf GD 362 1
نویسندگان
چکیده
We present trigonometric parallax observations of GD 362 obtained over seven epochs using the MDM 2.4m Hiltner Telescope. The existence of a dust disk around this possibly massive white dwarf makes it an interesting target for parallax observations. The measured parallax for GD 362 places it at a distance of 50.6 −3.1 pc, which implies that its radius and mass are ≈ 0.0106R⊙ and 0.71M⊙, respectively. GD 362 is not as massive as initially thought (1.2M⊙). Our results are entirely consistent with the distance and mass estimates (52.2 pc and 0.73M⊙) by Zuckerman et al., who demonstrated that GD 362 has a helium dominated atmosphere. Dropping GD 362 from the list of massive white dwarfs, there are no white dwarfs with M > 0.9M⊙ that are known to host circumstellar dust disks. Subject headings: stars: individual (GD 362, WD 1729+371) – white dwarfs
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