The CSNS accelerator successfully completed its 2021 summer maintenance and began a new round of machine study on Sept. 15.

Maintaining the accelerator with a tight schedule has always been a big challenge. The main tasks for this year were to install a new RF type ion source and finish commissioning, on-site replace the No. 12 drift tube of DTL-1, install the 16 RCS correction quadrupole magnets and 16 AC sextupole magnets as well as their power supplies, and refurbish the RCS injection area. Nevertheless, these extensive tasks were finished as planned, which helped pave the way for subsequent beam commissioning and increasing the beam power.

In addition, to continue the jobs that haven't been done during the last summer maintenance period, engineers also completed maintenance on 16 RCS quadrupole magnets and replacement of the leaky water cooling plates of the 4 ferrite loading cavity. Accomplishing these tasks was necessary to ensure stable operation.

Meanwhile, in a bid to save time for the overall maintenance plan and make sure the accelerator could be re-started as planned, the associated proton project team strove to install most of the equipment for this project. Routine maintenance on other hardware systems was also finished.

The linac was started Sept. 10, followed by the synchrotron Sept. 15. The accelerator has now begun machine study and is running at 100 kW, and the higher beam power commissioning is under way.