On the existence of young embedded clusters at high Galactic latitude

Abstract

Careful analyses of photometric and star count data available for the nine putative young clusters identified by Camargo et al. at high Galactic latitudes reveal that none of the groups contain early-type stars, and most are not significant density enhancements above the field level. Two-Micron All-Sky Survey (2MASS) colours for stars in the groups match those of unreddened late-type dwarfs and giants, as expected for the contamination by (mostly) thin disc objects. A simulation of one such field using only typical high-latitude foreground stars yields a colour–magnitude diagram that is very similar to those constructed by Camargo et al. as evidence for their young groups as well as the means of deriving their reddenings and distances. Although some of the fields are coincident with clusters of galaxies, one must conclude that there is no evidence that the putative clusters are extremely young stellar groups.