Brown dwarfs in young stellar clusters

Abstract

The present calculations of the early evolution of brown dwarfs and very low mass stars (LMSs) yield isochrones spanning 0.01-0.2 solar masses for ages in the 1 to 300 million year range. Since the brown dwarfs remain sharply segregated in T(eff) from LMSs for ages of less than 100 million years, it follows that for coeval populations of known age, a domain exists in the H-R diagram in which only brown dwarfs exist. These theoretical results are compared with recent observations of the Pleiades brown dwarf candidates, using two new sets of color-T(eff) transformations. Both sets yield consistent interpretations.