New dating of galactic open clusters.

A new set of isochrones for solar metallicity computed from models taking into account mass loss and moderate overshooting and using the recent opacity tables by Rogers and Iglesias (1992) has been used to determine the ages of 30 galactic open clusters covering an interval of age from 4 million to 9.5 billion years. The clusters collected here constitute an ensemble of homogeneous and accurate data, well discussed for distance, reddening, membership and binarity, and thus they provide a basic reference for age determinations. The present set of isochrones fits the observed color-magnitude diagrams of the clusters very accurately, and may thus be expected to provide reliable ages. Analytic relations between several characteristics of the isochrones and the age are given and can be used for further age calibrations consistent with this homogeneous scale.