Automated Quench Limit Test Procedure for Serial Production of XFEL RF Cavities

In the Accelerator Module Test Facility (AMTF) at DESY in Hamburg RF cavities and accelerating cryomodules are tested for the European X-ray Free Electron Laser (XFEL). Measurements are done by a team of physicists, engineers and technicians from The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences in Kraków, Poland, as a part of Polish in-kind contribution to the XFEL. The testing procedures providing information about maximum available gradient and heat loads measurement are performed for the high gradients (up to 31MV/m). During these tests the cavity deformation caused by the Lorentz force is compensated by piezo (fast) tuners. For this purpose automated high level software was developed. This paper describes a method used to tune automatically the cavities during the RF tests. It was validated with the XFEL cryomodules. This improvement was implemented into the testing software and it is successfully used for testing of serial production cavities