DEEP PHOTOMETRY IN THE CORE OF THE OPEN CLUSTER NGC-5606

The center of the open cluster NGC 5606 has been re-observed with broa d band UBVRI CCD photometry. Up to V = 18.5 likely cluster members are found underlining a sharp but not so populated cluster sequence. With this new photometry the cluster distance modulus is stated in V0 - M( v) = 11.90 (d = 2400 pc). The mean colour excess reaches the value [E( B-V)] = 0.51. The age of the cluster from the isochrone fitting is bet ween 6.3 10(6) and 7 10(6) y. Surprisingly enough there are not many s tars found below V = 15.5 in spite of the fact that we are observing t he very core of the cluster. This lack of faint cluster stars produces in turn a flat slope for the cluster mass spectrum. In this respect o ur computation yields x = 1.09 far enough of x = 1.35 which is assumed to be the slope characterizing the mass spectrum of galactic stars.