Successful RF and Cryogenic Tests of the SOLEIL Cryomodule

In the Storage Ring (SR) of the Synchrotron SOLEIL light source, two cryomodules will provide the maximum power of 600 kW required at the nominal energy of 2.75 GeV with the full beam current of 500 mA and all the insertion devices. A cryomodule prototype, housing two 352 MHz superconducting single-cell cavities with strong damping of the Higher Order Modes (HOM) was built and successfully tested in the ESRF. Even though the achieved performance (3 MV and 380 kW) did meet the SOLEIL requirement for the first year of operation, it was decided to upgrade the cryomodule prototype before its implementation on the SR. Modifications of the internal cryogenic system as well as the input power and dipolar HOM couplers required full disassembling, reassembling and testing of the cryomodule, which were carried out at CERN. The refurbishment and test program, which was achieved in the framework of a collaboration between SOLEIL, CEA and CERN, is reported in this paper. A 2 nd cryomodule, similar to the modified prototype, shall be implemented on the SR by the end of 2006.