A Numerical Simulation Study of Mass Segregation in Embedded Stellar Clusters

摘要

The initial condition of the formation of massive stars is still unclearat present. In particular, it is still debatable whether or not massive stars areformed in the cluster center. Some people considered from the viewpoint of timescale and thought that the mass segregation phenomena in embedded clustersmeans that the massive stars can only be born in the cluster center. In this paperwe used the Monte Carlo method to snake numerical simulation of the dynamicalevolution of embedded clusters and the result is compared with the observations.It is assumed that at the initial time massive stars are randomly distributed. Itwas found that, due to the random motions of massive stars, temporary masssegregation may exist at certain times in the course of evolution of a givenembedded cluster, and this phenomenon may be very prominent in some ofthem. It is pointed out that massive star formation in the center is not the onlyexplanation for mass segregation in embedded clusters. In addition, dynamicalfriction from the gas can effectively reduce the time scale of the dynamical masssegregation. In consequence, the probability of temporary mass segregation isincreased.