Abstract

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 approximately 7x10-4 M middle dot in circle pc-3 inferred from this survey. With the caveat that the sample size is very small, it appears that a significant fraction, approximately 10%, of the local dark matter halo is in the form of very old, cool, white dwarfs.

Keywords

HaloWhite dwarfAstrophysicsProper motionPhysicsAstronomyDark matter haloMassive compact halo objectDark matterBlue dwarfGalactic haloStarsBlack dwarfWhite (mutation)GalaxyChemistry

Affiliated Institutions

Related Publications

Is Galactic Dark Matter White?

We calculate the expected white dwarf luminosity functions and discovery functions in photometric passbands, if these stellar remnants provide a substantial fraction of the soug...

1999 The Astrophysical Journal 67 citations

Publication Info

Year
2000
Type
article
Volume
532
Issue
1
Pages
L41-L45
Citations
87
Access
Closed

Social Impact

Social media, news, blog, policy document mentions

Citation Metrics

87
OpenAlex
8
Influential
75
CrossRef

Cite This

Rodrigo Ibata, M. J. Irwin, O. Bienaymé et al. (2000). Discovery of High Proper-Motion Ancient White Dwarfs: Nearby Massive Compact Halo Objects?. The Astrophysical Journal , 532 (1) , L41-L45. https://doi.org/10.1086/312566

Identifiers

DOI
10.1086/312566
PMID
10702128
arXiv
astro-ph/0002138

Data Quality

Data completeness: 84%