The Field Measurement of the Injection Painting Bump Magnets for CSNS/RCS

For accumulating high-intensity beam, the H-stripping injection is adopted in the rapid cycling synchrotron (RCS) of China Spallation Neutron Source. Painting injection is a key solution, which is performed in a straight section of RCS by eight bump magnets, four for horizontal painting and four for vertical painting. The fabrication and the field measurement of the magnets have been completed. The measurement of the central magnetic field and the integral magnetic field was done by a small searching coil and a long searching coil, respectively. The measurement system and the results of the magnetic field measurement are presented in this paper. The results show that the magnets fulfil the design specification.