SCYON Abstract

Received on June 24 2005

Photometric study of the old open clusters Berkeley 73, Berkeley 75 and Berkeley 25

AuthorsG. Carraro(1), D. Geisler(2), A. Moitinho(3), G. Baume(4), R. Vazquez(4)
Affiliation(1) UChile/Yale
(2) Concepcion
(3) Lisboa
(4) La Plata
Accepted byAstronomy & Astrophysics
Contactgcarraro@das.uchile.cl
URLhttp://fr.arxiv.org/abs/astro-ph/0506596
Links

Abstract

CCD BVI photometry of the faint open clusters Berkeley 73, Berkeley 75 and Berkeley 25 are presented. The two latter are previously unstudied clusters to our knowledge. While Berkeley 73 is found to be of intermediate-age (about 1.5 Gyr old), Berkeley 75 and Berkeley 25 are two old clusters, with ages larger than 3.0 Gyr. We provide also estimates of the clusters size. Very interestingly, all these clusters turn out to lie far away from the Galactic Center, at RGC < 16 kpc, and quite high onto the Galactic plane, at |ZO| > 1.5 kpc. They are therefore important targets to probe the properties of the structure of the Galaxy in this direction, where the Canis Major over-density has been recently discovered to be located