Development of the Accsim tracking and simulation code

Accsim is a synchrotron/storage-ring tracking and simulation program that was originally written to simulate charge-exchange injection and accumulation of an intense proton beam in a KAON factory accumulator ring. It has subsequently been developed and used for other injection studies and for applications such as the optimization of collimation systems. The code performs basic six-dimensional tracking of an ensemble of particles in a magnet lattice and incorporates models for various processes such as multiturn injection, phase-space painting, RF capture, space-charge effects, interactions with stripping foils and collimators, and tabulation of particle losses and beam form factors. After a brief review of Accsim's architecture and basic design, this paper gives an update on the current status of the code and describes the more recent additions that have been made.