Direct Detection of Galactic Halo Dark Matter
Abstract
The Milky Way Galaxy contains a large, spherical component which is believed to harbor a substantial amount of unseen matter. Recent observations indirectly suggest that as much as half of this ``dark matter'' may be in the form of old, very cool white dwarfs, the remnants of an ancient population of stars as old as the Galaxy itself. We conducted a survey to find faint, cool white dwarfs with large space velocities, indicative of their membership in the Galaxy's spherical halo component. The survey reveals a substantial, directly observed population of old white dwarfs, too faint to be seen in previous surveys. This newly discovered population accounts for at least 2% of the halo dark matter. It provides a natural explanation for the indirect observations, and represents a direct detection of Galactic halo dark matter.
Keywords
Cite
@article{arxiv.astro-ph/0104293,
title = {Direct Detection of Galactic Halo Dark Matter},
author = {B. R. Oppenheimer and N. C. Hambly and A. P. Digby and S. T. Hodgkin and D. Saumon},
journal= {arXiv preprint arXiv:astro-ph/0104293},
year = {2009}
}
Comments
13 pages, 4 figures, 1 table. Note added after Science Express online publication: This text reflects the correction of a few typographical errors in the online version of the table. It also includes the new constraint on the calculation of d_max which accounts for the fact that the survey could not have detected stars with proper motions below 0.33 arcseconds per year. Published online at ScienceExpress www.sciencemag.org 22 March 2001; 10.1126/science.1059954; To appear in Science 27 April 2001