Observed Dynamical Parameters of Star Clusters in the SMC

Abstract

The dynamical study of the SMC clusters is very important for many reasons. (a) The disk “blue” clusters are more massive and older than the galactic open clusters whereas the “halo” red clusters are less massive and younger than the galactic globulars (Kontizas, Danezis, Kontizas, 1982; Kontizas and Kontizas, 1983). (b) All clusters show density profiles that fit the available theoretical models (King, 1962) giving evidence of relaxed systems, even for the young clusters with evolutionary ages 10⁶–10⁸yr. The relaxation mechanism has to be reconsidered for the SMC and possibly in connection to the metal abundance. (c) The ellipticities of young and old SMC clusters have shown that there is no obvious age-ellipticity dependance and that the SMC clusters are statistically more elliptical than the clusters of the LMC and our Galaxy (Frenk and Fall, 1982, Kontizas et al, 1984).