SCYON Abstract

Received on March 24 2005

The intermediate-age open clusters Ruprecht 4, Ruprecht 7 and Pismis 15

AuthorsG. Carraro (1), D. Geisler (2), G. Baume (3), R. Vazquez (3), A. Moitinho (4)
Affiliation1 UChile/Yale
2 Concepcion
3 La Plata
4 Lisboa
Accepted byMonthly Notices of the Royal Astronomical Society
Contactgcarraro@das.uchile.cl
URLastro-ph/0503550>
Links Ruprecht 7 = Berkeley 33

Abstract

We report on BVI CCD photometry to V=22.0 for 3 fields centeredon the region of the Galactic star clusters Ruprecht 4, Ruprecht 7 and Pismis 15 and on 3 displaced control fields. Ruprecht 4 and Pismis 15 have never been studied before, and we provide for the first time estimates of their fundamental parameters, namely, radial extent, age, distance and reddening. Ruprecht 7 (Berkeley 33) however was studied by Mazur et al. (1993). We find that the three clusters are all of intermediate age (0.8-1.3 Gyr), and with a metallicity close to or lower than solar.