Cryomodule 2 returns to NML

A crane lowers Cryomodule 2 onto the ground floor of NML. It is now installed in the Advanced Superconducting Test Accelerator. Photo: Jerry Leibfritz

After a long hiatus to repair an internal helium leak, Cryomodule 2 was recently re-installed in the Advanced Superconducting Test Accelerator at NML. Since its return to NML, there has been a flurry of activity getting all of the systems connected and commissioned in preparation for operation. The coupler and cavity string vacuum work is complete, and welding of the cryogenic interconnect circuits is under way. Initial conditioning of the cavity couplers with radio-frequency power has also begun. The installation and commissioning activities are expected to wrap up in June, at which time the cryomodule will be ready to cool down to cryogenic temperatures for full power operation. CM2 is anticipated to be the first high-gradient Tesla Type-III+ cryomodule in which all of the cavities meet the requirements of the proposed International Linear Collider, operating at 31.5 MeV per meter.