First cryogenics operational experience of the ESS cryomodules in LINAC configuration

This paper presents the first operational experience of the European Spallation Source (ESS) cryomodules in a linac configuration, with a focus on the challenges encountered during the initial integrated cooldown and subsequent stable operation. Key aspects such as thermal stability, cryogenic performance, and system integration are discussed in detail. The paper also highlights lessons learned during the operation, identifies areas for improvement, and proposes strategies for optimizing cryogenic operations in the upcoming phases of the ESS project.