SIMBAD references

We report BV Johnson CCD photometry of 2498 stars in the region of the poorly studied open cluster NGC 4815. This object appears in the Janes (1988) list of possible old open clusters. NGC 4815 lies in the galactic plane, in a region of strong absorption. The color magnitude diagram (CMD) we derive shows that NGC 4815 has about the Hyades age (5x10⁸yr) and a probable lower than solar metal abundance. The color excess E_B–V and the distance modulus (m-M) turn out to be 0.70 and 14.10, respectively. Accordingly a distance of 2.5 Kpc from the Sun is derived. The luminosity function (LF) we obtain for the main sequence (MS) stars is consistent with a Salpeter (x=1.55) initial mass function (IMF).