Dynamical Models of Star Formation and the Initial Mass Function

Abstract

Numerical simulations highlight that star formation is a dynamical process in which stars interact during their formation. Of particular interest is that accretion in a clustered environment is non-uniform in that stars located in the centre of the potential accrete more and become more massive. This competitive accretion process can explain the initial mass function of stars, including a shallow slope for low-mass stars and a steeper Salpeter-like slope for higher-mass stars. Numerical simulations of the fragmentation and formation of a stellar cluster show that the final stellar masses are due to competitive accretion and that this results in a realistic IMF. Competitive accretion also naturally results in a direct correlation between the richness of a cluster and the mass of the most massive star therein. Shallower IMFs are possible if the Jeans mass is significantly higher than one M_⊙.