The operation and improvement of CSNS front end

Introduction Operation target beam power of China Spallation Neutron Source (CSNS), as the China’s first 100 kW beam power pulsed neutron source, is now larger than 80 kW. During the beam power upgrading process of CSNS to 50 kW from 2018 to 2019, many improvements have been made for the front end of CSNS. Results The improvements mainly focus on solving the problems of ion source instability and the radio frequency quadrupole (RFQ) sparking caused by the pre-chopped beam into RFQ.