Astrophysics, abstract
astro-ph/0606718

From: Beatriz Barbuy Prof [view email]

Date: Thu, 29 Jun 2006 12:33:57 GMT (465kb)

AL 3 (BH 261): a new globular cluster in the Galaxy

Authors: S. Ortolani, E. Bica, B. Barbuy

Comments: 6 figures. Astrophysical Journal Letters, in press

AL~3 (BH 261), previously classified as a faint open cluster candidate, is shown to be a new globular cluster in the Milky Way, by means of B, V and I Color-Magnitude Diagrams. The main feature of AL~3 is a prominent blue extended Horizontal Branch. Its Color-Magnitude Diagrams match those of the intermediate metallicity cluster M~5. The cluster is projected in a rich bulge field, also contaminated by the disk main sequence. The globular cluster is located in the Galactic bulge at a distance from the Sun d$_{\odot}$ = 6.0$\pm$0.5 kpc. The reddening is E(B-V)=0.36$\pm$0.03 and the metallicity is estimated to be [Fe/H] $\approx$ -1.3$\pm$0.25. AL~3 is probably one of the least massive globular clusters of the Galaxy.

http://arxiv.org/abs/astro-ph/0606718