Photometric catalog of nearby globular clusters. II. A large homogeneous (V,I) color-magnitude diagram data-base

In this paper we present the second and nal part of a large and photometrically homogeneous CCD color-magnitude diagram (CMD) data base, comprising 52 nearby Galactic globular clusters (GGC) imaged in the V and I bands. The catalog has been collected using only two tele- scopes (one for each hemisphere). The observed clus- ters represent 75% of the known Galactic globulars with (m M)V 16:15 mag, cover most of the globular clus- ter metallicity range ( 2:2 (Fe=H) 0:4), and span Galactocentric distances from 1: 2t o 18: 5k pc. In particular, here we present the CMDs for the 13 GGCs observed in the Northern hemisphere. The remaining 39 Southern hemisphere clusters of the catalog have been presented in a companion paper (Rosenberg et al. 2000). We present the rst CCD color magnitude diagram for NGC 6779 (M 56). All the CMDs extend from at least 2 magnitudes below the turn-o (i.e. Vlim 22) to the tip of the red giant branch. The calibration has been done using a large number of standard stars, and the absolute calibration is reliable to a 0:02 mag level in both lters. This catalog, because of its homogeneity, is expected to represent a useful data base for the measurement of the main absolute and relative parameters characterizing the CMD of GGCs.