Direct N-Body Simulations with a Recursive Center of Mass Reduction and Regularization

Abstract

We report on an investigation of the core collapse of an initially bound system of 1024 point masses based on a new numerical method which incorporates a recursive center of mass reduction of the N-body system and includes regularization of the two body encounters. A tree which organizes the point masses into a logarithmic hierarchy is the primary feature of the numerical algorithm. The spatial structure of the tree allows for rapid force calculation while the associated temporal structure allows for variable time steps. Simulations are calculated for several core collapse times in an effort to follow the end point evolution of the system. The point-like nature of the interactions are maintained throughout the simulations.