Abstract:
We present a detailed study of four young open star clusters and two OB associations using deep CCD UBVRI and 2MASS JHK measurements. Physical parameters of the clusters have been estimated using optical as well as near IR data. Ages of objects under study range 10-100 Myr. Mass function slope of the sample of clusters are in agreement with the Salpeter (1955) value. From a comparison of mass function slope of clusters and OB associations in our Galaxy with those in external galaxies, we urgue that the star formation processes are such that they yield almost similar stellar mass distribution in vastly different star forming environments.