Photometry of Southern Globular Clusters-II: BRIGHT STARS IN NGC 6752

Abstract

Photoelectric UBV data are presented for nearly 100 stars with V ≤ 16 in NGC 6752. The cluster has reddening E ( B−V ) = 0.05 mag and distance modulus ( m−M ) ≈ 13.5. The cluster giant branch shows a clear separation into ‘normal’ and ‘asymptotic’ branches, although the latter seems to consist rather of a series of clumps. The variation of ultra-violet excess with magnitude along the giant branches agrees with that expected from changes in surface gravity. One new small amplitude red variable has been detected.