Recalculation of the HIRFL-SSC injection and extraction system

Abstract：

In order to further improve beam transmission efficiency at the SSC, the beam center trajectory and injection and extraction system are recalculated based on the program group used in the final design of the GANIL accelerator, with some necessary changes and the addition of some auxiliary programs. The two different types of injection and extraction elements (the bending magnet and the inductive septum) are distinguished, and their interaction with the ambient field is considered. More focus is placed on considering the differences in the magnet field inhomogeneity of the ambient field in the located area of the inductive septum where the ends are situated in the ambient field (between the main magnet poles). Thus the gradient magnetic field problem of the inductive septum is solved perfectly. As well as preparing the necessary auxiliary programs and taking the structural integration of the SSC magnetic field maps, the measured magnet field correction is completed. Therefore, the trajectory and a variety of injection and extraction system parameters are obtained. According to the recalculation results, the SSC beam transmission efficiency will be enhanced significantly.