Speaker
Description
Closed orbit distortion (COD) is a critical factor affecting accelerator performance, and realignment serves as an effective measure to mitigate COD and reduce beam loss. The Rapid Cycling Synchrotron (RCS) of the China Spallation Neutron Source (CSNS) currently suffers from significant beam orbit distortion, particularly in the horizontal plane, which limits its operational efficiency. To address this issue, a systematic analysis was conducted using the MADX accelerator physics simulation program, based on the alignment measurement data obtained in the summer of 2025. Through evaluation of alignment errors and comparison of different adjustment schemes, an optimized realignment strategy was proposed, involving transverse adjustments of four quadrupole magnets. Theoretical simulation results indicate that after realignment, the horizontal orbit distortion can be reduced by approximately 2 mm, and the vertical distortion by about 4 mm, leading to a significant improvement in overall orbit smoothness. Subsequent beam tests further validated the effectiveness of the strategy. The horizontal orbit was reduced by approximately 6 mm, and the vertical orbit by about 2 mm, compared with the pre-alignment state. This study fully confirms the critical role of realignment in optimizing beam orbit performance.
| Paper status | Resubmitted proceeding files received and assigned to an editor. Accepted by Submitter. |
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