Abstract:
We present the VI CCD photometric observations of about 5500 stars up to a limiting magnitude of V~ 20 in an area of ~16'⨯16' around the cluster NGC 6631. The cluster parameters determined for the first time by fitting the theoretical isochrones in the V, (V – I) diagram of the cluster stars are E(V – I) = 0.60±0.05 mag, distance = 2.6± 0.5 kpc, age = 400±100 Myr and metallicity, Z= 0.05. The cluster diameter determined from the radial density profile is 4.8± 0.5 pc. The mass function of the cluster has a slope of 2.1± 0.5.
