Globular cluster populations of Hickson compact groups

Abstract

We present deep V and R band CCD photometry of the globular cluster systems of Hickson compact group galaxy 22a (NGC 1199) and 90c (NGC 7173), taken with the European Southern Observatory's New Technology Telescope (NTT). Globular cluster populations were detected in both galaxies, with HCG 22a having a specific frequency of S_N ~ 2 and HCG 90c having a value of S_N ~ 4. Both values of specific frequency are consistent with the average value found for field ellipticals. These results give rise to two possible scenarios for globular cluster formation in these galaxies; (a) globular clusters formed during the time when their parent galaxy was simply a 'field' galaxy, or (b) mergers are not important in the formation of globular clusters in Hickson compact groups (Hickson compact groups arc expected to have high merger rates due to their large densities and low velocity dispersions).