European Spallation Source begins cold conditioning in accelerator

The European Spallation Source (ESS) has reached a significant milestone with the commencement of cold radio frequency (RF) conditioning in its accelerator, operating at 2 Kelvin (-271 degrees Celsius). This phase is crucial for enabling the accelerator's cavities to become superconducting, a state necessary for efficient proton beam acceleration.

Following the successful cooldown of all 27 cryomodules and the cryogenic distribution system to 4 Kelvin, ESS is now focusing on the next step: RF power conditioning at the ultra-low temperature of 2 Kelvin. At this temperature, cavities achieve superconductivity, allowing them to conduct electricity with zero resistance. This dramatically enhances efficiency and permits accelerator operation with minimal energy loss.

The cooldown to 4 Kelvin was completed as planned, supervised by the Local Control Room in collaboration with teams from the Accelerator, Integrated Control Systems (ICS), and Main Control Room. The complex process was guided by an automatic control sequence developed by the SRF and ICS teams.

ESS Director General Helmut Schober commended the team's achievement, highlighting the dedication and expertise demonstrated. The facility is now preparing to send a proton beam through the Superconducting Linac to the Tuning Beam Dump in the first quarter of 2025.