Beam dynamics studies for the SBLC

In linear accelerators, wake field effects and dispersion from orbit distortions can lead to considerable emittance dilution. Since the transverse wake fields and the dispersion depend on the orbit in the accelerating structures and quadrupoles, there are constraints on the resolution of the beam position monitors and on alignment tolerances. The tracking code L, which is affiliated to the family of MAFIA codes, has been developed to simulate both single and multi-bunch dynamics in linear accelerators. By use of this code, the impact of misalignments on the combined single and multi-bunch behaviour of the beam is investigated for the S-band accelerator as envisioned in the SBLC study. Further, the performance of a full machine tuning scheme including beam loading compensation, orbit correction, structure adjustment and emittance correction is examined. From the results, limits for the alignment tolerances are deduced.