UBVRI CCD photometry of the old open cluster NGC 6253

Abstract
We present UBVRI photometry for the old open cluster NGC 6253. From comparison of the observed colour-magnitude diagrams with simulations based on stellar evolutionary models we derive in a self-consistent way the reddening, the distance and the age of the cluster: E(BV) = 0.23-0.32, (m—M)0 = 10.9 ±0.1, with metallicity approximately double the solar value and age ≃3 Gyr. The cluster has a binary sequence, discernible even through the field contamination, suggesting that about 1/3 of the cluster members belong to binary, or multiple, systems.

This publication has 0 references indexed in Scilit: