Cryogenic Tests of SHINE Superconducting Quadrupole Magnets in the Multifunction Test Facility

Shanghai HIgh repetitioN rate XFEL and Extreme light facility (SHINE) is a 3 km long advanced X-ray source facility. The main superconducting Linear Accelerator (Linac) of SHINE can increase the electron beam energy up to 8 GeV under superconducting (SC) continuous wave (CW) mode. SHINE Linac is mainly based on the seventy-five 1.3 GHz-cavity cryomodules which are connected in series in 1.4 km and operated at superfluid helium temperature of 2 K. Each cryomodule mainly consists of 8 Superconducting Radio Frequency (SRF) cavities, 8 high power couplers, 8 tuners, one cold Beam Position Monitor (BPM) and one superconducting quadrupole (SCQ) magnet. In order to ensure the cryomodules stable operation at 2 K in the Linac tunnel, all the key elements are required to be tested at cryogenic temperatures before their assembly into the cryomodule. A Multifunction Test Facility (MTF) is designed and fabricated, by referring to the 3-cryogenic circuit design for the cryomodule (2 K, 5 K and 45 K) as well as the compatible consideration for all other cryomodules key elements cryogenic tests. SCQ magnet, as designed to work at liquid helium temperature by conduction-cooling, is thus necessary to be carried out on the performance tests in the MTF. This paper will give a detailed description of the MTF, as well as the cryogenic commissioning and test results for the facility itself. The experimental issues related to cryogenic tests of the SCQ magnets, such as the conduction-cooling performance and the cryogenic stability for current tests, are also discussed.