The dynamic decay of young few-body stellar systems

We investigate the dynamic decay of nonhierarchical few-body systems, with an emphasis on applications to young stellar multiples formed by fragmenting cloud collapse. A chain regularization scheme is used to integrate orbits for 300 or more crossing times in order to guarantee that most systems are fully decayed. In this paper, we consider cases where the number N of point-mass stars is three, four, or five; and we explore effects of the stellar mass spectrum on the outcome in the low angular momentum limit. A novel classification scheme is introduced to identify the remnant decay products, including singles, binaries, and bound hierarchical multiples. The ensemble of final system configurations is then analysed to determine mass and escape speed distributions, and to characterize properties of the binary and triple stars formed during the decay. Some statistical features of the endstates can be understood analytically using well-known principles of few-body dynamics. Our results suggest observable signatures in and around star forming regions which would be expected if multiply fragmenting collapse is a common mode of star formation.