Field Quality Change in Accelerator Magnets Due to Re-Magnetization of Superconductor

Magnetic field decay of superconducting magnets during the particle injection period and subsequent snapback, which is a rapid magnetic field change at the beginning of acceleration, are issues to be solved for stable operation of high-energy accelerators. In order to simulate and understand the phenomena, we made model calculations using a Monte Carlo method. The calculation results were consistent with the magnetic field measurement results of periodic magnetic patterns and the allowed multipole field drift. Using our simulation we also investigated the impact of conductor magnetization on these effects. We calculated the scaling law that predicts the snapback parameters and may be adopted for rapid magnetic field correction in superconducting accelerators. We report the simulations and the analysis