SCYON Abstract

Received on April 13 2005

Metal abundances in extremely distant Galactic old open clusters. II. Berkeley 22 and Berkeley 66

AuthorsSandro Villanova (1), Giovanni Carraro (2), Fabio Bresolin (3), Ferdinando Patat (4)
Affiliation(1) Padova
(2) UChile/Yale
(3) IfA
(4) ESO
Accepted byAstronomical Journal
Contactgcarraro@das.uchile.cl
URLastro-ph/0504282
Links Berkeley 22 Berkeley 66

Abstract

We report on high resolution spectroscopy of four giant stars in the Galactic old open clusters Berkeley 22 and Berkeley 66 obtained with HIRES at the Keck telescope. We find that [Fe/H] = -0.32 ± 0.19 and [Fe/H] = -0.48 ± ± 0.24 for Berkeley 22 and Berkeley 66, respectively. Based on these data, we first revise the fundamental parameters of the clusters, and then discuss them in the context of the Galactic disk radial abundance gradient. We found that both clusters nicely obey the most updated estimate of the slope of the gradient from Friel et al (2002) and are genuine Galactic disk objects.