Stellar Velocity Dispersion of the Leo A Dwarf Galaxy
Abstract
We measure the first stellar velocity dispersion of the Leo A dwarf galaxy, σ=9.3+/-1.3 km s-1. We derive the velocity dispersion from the radial velocities of 10 young B supergiants and two H II regions in the central region of Leo A. We estimate a projected mass of (8+/-2.7)×107 Msolar within a radius of 2' and a mass-to-light ratio of at least 20+/-6 Msolar/Lsolar. These results imply Leo A is at least ~80% dark matter by mass.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2007
- DOI:
- 10.1086/519547
- arXiv:
- arXiv:0705.1093
- Bibcode:
- 2007ApJ...666..231B
- Keywords:
-
- Galaxies: Individual: Name: Leo A;
- Astrophysics
- E-Print:
- 6 pages, accepted to ApJ