Beam dynamics studies in a TESLA positron pre-accelerator

Abstract

The TESLA linear collider is based on superconducting accelerating cavities. Behind the positron production target normal conducting cavities have to be used in order to cope with high particle losses and with focusing solenoid surrounding the cavities. The main purpose of this pre-accelerator is to provide maximum capture efficiency for the useful part of the totally acceptable positron beam with technically reasonable parameters of the linac. The coupled optimization of the capture optics behind the target and pre-accelerator rf-operation has been carried out. The beam dynamics simulation results as well as the pre-accelerator peculiarities are presented.