EROS 2 proper motion survey: Constraints on the halo white dwarfs
Abstract
We are conducting a 377.2o proper motion survey in the ~ V and I bands in order to determine the cool white dwarf contribution to the Galactic dark matter. Using the 250.2o for which we possess three epochs, and applying selection criteria designed to isolate halo-type objects, we find no candidates in a 5500 pc3 effective volume for old, fast MV=17 white dwarfs. We check the detection efficiency by cross-matching our catalogue with \citeauthor{Luy79b}'s NLTT catalogue. The halo white dwarf contribution cannot exceed 5% (95% C.L.) for objects with MV=17 and 1<= V-I<= 1.5. The same conclusion applies to a 14 Gyr halo composed of white dwarfs with hydrogen atmosphere, as modeled by \citeauthor{Cha99}. Based on observations made with the Marly telescope, located at the European Southern Observatory, La Silla, Chile.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- July 2002
- DOI:
- 10.1051/0004-6361:20020827
- arXiv:
- arXiv:astro-ph/0205537
- Bibcode:
- 2002A&A...389L..69G
- Keywords:
-
- Galaxy: halo;
- Galaxy: kinematics and dynamics;
- dark matter;
- white dwarfs;
- Astrophysics
- E-Print:
- 5 pages, 2 postscript figures, accepted for publication in A&