Description
We present new CCD photometry of the distant old open star cluster Berkeley 32 in Johnson V and Cousins I passbands. A total of about 3200 stars have been observed in a field of about 13'x13'. The colour-magnitude diagram (CMD) in V, (V-I) has been generated down to V=22mag. A broad but well defined main sequence is clearly visible. Some blue stragglers, a well developed subgiant branch and a Red Clump are also seen. By fitting isochrones to this CMD as well as to other CMDs available in the literature, and using the Red Clump location, the reddening, distance and age of the star cluster have been determined. The cluster has a distance of about 3.3kpc, its radius is about 2.4pc; the reddening E(B-V) is 0.08 mag and the age is about 6.3Gyr. By comparison with theoretical isochrones, a metallicity of [Fe/H]~-0.2dex has been estimated.
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