The cryogenic system for the China Spallation Neutron Source (CSNS) cryogenic system was operated successfully over four weeks from August 16^th.

Cooling of the CSNS cryogenic system was started on August 16^th. After 25 hours, the temperature of the whole system had decreased smoothly to 18K. The heater of the hydrogen circulation cold box was loaded to 700 W, then the cryogenic system was switched to a stable state and send out the ‘Ready’ signal.

On August 28^th, a neutron beam was successfully obtained at CSNS for the first time. The cryogenic system worked steadily, and satisfied the requirements for neutron physics. After targeting, the cryogenic system kept running and the two hydrogen pumps were tested separately and proved stable.

First operation results showed that the performance of the cryogenic system met the technical specifications and requirements.

The cryogenic system was warmed up again on September 13th, completing the first round of testing. The stability and reliability of the CSNS cryogenic system were tested and proven. Experience gained during this operation period will lay a solid foundation for long-term stable operation in the future. For the next step, the CSNS cryogenic system will run in conjunction with beam tuning for the target station and spectrometer.