Young stellar groups in M 33 galaxy: delineation and main parameters

Abstract

The problem of (non-)existence of a typical size of the stellar associations is revisited by use of deep UBVRI stellar CCD photometry in M 33 from the Local Group Survey (Massey et al. 2006). We compare the outlines of the `classical OB associations' (Ivanov 1991) with stellar groups that were selected through an objective method for determination of the local stellar density and delineation. Main parameters of some stellar groups like size, shape and density concentrations are determined.