After 10 months of high-quality operation, the China Spallation Neutron Source (CSNS) accelerator was shut down for annual summer maintenance on July 20.

It is the first time for CSNS to operate at 100 kW for a whole operation round from 10 October 2020 to 20 July 2021. The beam time for this operation round reached 4898 hours in total, 183 hours more than the previous round. In addition, the beam availability increased to 94.5%. These operational performances indicate that CSNS accelerator operates at an international advanced level compared to other neutron facilities in the world. The successful operation results from the efforts made during the summer maintenance in 2020, such as the hardware improvement and efficient maintenance, as well as increasing operational skills.

For this year, in addition to scheduled routine maintenance, a new RF ion source will be installed to replace the old penning ion source, and new trim quadrupole and AC sextupole magnets will be installed in the RCS. These measures aim to improve operation availability and further increase the beam power, and will be one of the key steps of the CSNS Phase-II project.

In the next operational round, the beam power is expected to increase by more than 30%.