CCD photometry of the unstudied galactic star clusters Be 10, Be 67 and To 5

Abstract

We present the broad band Johnson U BV and Cousins RI CCD photometric observations for open clusters Be 10, Be 67 and To 5. So far no photometric study of these clusters is published. The colour-magnitude diagrams indicate that all the three clusters are of intermediate age. The reddening E0B-V), estimated from colour-colour diagrams/ colour-magnitude diagrams, is 0.87±0.05 mag for Be 10, 0.79±0.005 mag for Be 67 and 0.80±0.05 mag for To 5. The comparison of colour magnitude diagrams with the stellar models with convective overshoot by Girardi et al. (2002) produces a good fit for a metallicity Z=0.008 for cluster Be 10 and Z=0.02 for clusters Be 67 and To 5. Ages for Be 10, Be 67 and To 5 are log (ag) = 8.8±0.1, 9.0±0.1 and 8.3±0.2 respectively. The corresponding distances for these clusters are 2.29±0.21, 2.45±0.23 and 1.75±0.16 kpc respectively. Analysis of the radial distribution of stellar surface density indicates that radius values for Be 10, Be 67 and To 5 are 6.0, 3.5 and 6.0 arcmin respectively.