Discovery of high proper-motion ancient white dwarfs:: Nearby massive compact halo objects?

被引：95

作者：

Ibata, R

Irwin, M

Bienaymé, O

Scholz, R

Guibert, J

机构：

[1] Max Planck Inst Astron, D-69117 Heidelberg, Germany

[2] Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England

[3] Observ Strasbourg, F-67000 Strasbourg, France

[4] Inst Astrophys, D-14482 Potsdam, Germany

[5] INSU, Ctr Anal Images, F-75014 Paris, France

[6] Observ Paris, DASGAL, UMR 8633, F-75014 Paris, France

来源：

ASTROPHYSICAL JOURNAL | 2000年 / 532卷 / 01期

关键词：

dark matter; Galaxy : halo; solar neighborhood; white dwarfs;

D O I：

10.1086/312566

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We present the discovery and spectroscopic identification of two very high proper-motion ancient white dwarf stars, found in a systematic proper-motion survey. Their kinematics and apparent magnitude clearly indicate that they are halo members, while their optical spectra are almost identical to the recently identified cool halo white dwarf WD 0346+246. Canonical stellar halo models predict a white dwarf volume density that is 2 orders of magnitude less than the rho similar to 7 x 10(-4) M-circle dot pc(-3) inferred from this survey. With the caveat that the sample size is very small, it appears that a significant fraction, similar to 10%, of the local dark matter halo is in the form of very old, cool, white dwarfs.

引用

页码：L41 / L45

页数：5

共 23 条

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