Modeling of space-charge phenomena in multi-turn tracking

Although many space-charge simulations have been developed for linacs, beamlines, and idealized rings, there are relatively few simulation codes applicable to multi-turn tracking with space charge in a realistic synchrotron or accumulator/storage ring lattice. Recently the program ACCSTM, used for accumulator-ring injection studies anti other applications, has been upgraded with improved transverse space charge models: one using a conventional multiple-Fourier-transform (MFT) method and another using a new hybrid fast-multipole (HFM) algorithm. After an overview of their implementation in the ACCSTM code, we present tests and observations of how well various space-charge phenomena can be be produced by the HFM models.