The Tucana dwarf Galaxy.
Abstract
We present deep CCD photometry for the dwarf galaxy in Tucana (l=323, b=-47.4). The data indicate that the galaxy is dominated by an intermediate/old stellar population with metallicity similar to that of the galactic globular clusters NGC 6752 and NGC 7089 (M2) (we find [Fe/H]=~-1.56). The distance modulus we derived, (m-M)_V_=~24.72+/-0.2, makes clear that this galaxy belongs to the Local Group. Tucana is clearly different from other dwarf galaxies, such as Leo I (Lee et al. 1993b), or Phoenix (Ortolani and Gratton 1988), because there is no evidence of a young stellar population (t<=5Gyrs) We suggest that the Tucana Galaxy is a genuine dwarf spheroidal in which no recent burst of star formation occurred.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- June 1996
- DOI:
- 10.48550/arXiv.astro-ph/9511144
- arXiv:
- arXiv:astro-ph/9511144
- Bibcode:
- 1996A&A...310..715C
- Keywords:
-
- STARS: HR-DIAGRAMS;
- STARS: LUMINOSITY FUNCTIONS;
- GALAXIES: ELLIPTICAL;
- GALAXIES: STELLAR CONTENT;
- GALAXIES: TUCANA DWARF;
- Astrophysics
- E-Print:
- 4 pages, 3 Postscript figures. To appear in The Proceedings for the "Formation of the Galactic Halo...Inside and Out"