MASS DISTRIBUTIONS OF STARS AND CORES IN YOUNG GROUPS AND CLUSTERS

Abstract

We investigate the relation of the stellar initial mass function (IMF) and\nthe dense core mass function (CMF), using stellar masses and positions in 14\nwell-studied young groups. Initial column density maps are computed by\nreplacing each star with a model initial core having the same star formation\nefficiency (SFE). For each group the SFE, core model, and observational\nresolution are varied to produce a realistic range of initial maps. A\nclumpfinding algorithm parses each initial map into derived cores, derived core\nmasses, and a derived CMF. The main result is that projected blending of\ninitial cores causes derived cores to be too few and too massive. The number of\nderived cores is fewer than the number of initial cores by a mean factor 1.4 in\nsparse groups and 5 in crowded groups. The mass at the peak of the derived CMF\nexceeds the mass at the peak of the initial CMF by a mean factor 1.0 in sparse\ngroups and 12.1 in crowded groups. These results imply that in crowded young\ngroups and clusters, the mass distribution of observed cores may not reliably\npredict the mass distribution of protostars which will form in those cores.\n