Conditioning of the Power Couplers for the ESS Elliptical Cavity Prototypes

Abstract

International audienceIn the framework of the European Spallation Source (ESS), some power couplers have been designed and manufactured to supply, with RF power, the medium-beta (β=0.67) elliptical cavities of the cryomodule demonstrator. The power couplers work at 704.4 MHz and are tested up to 1.2 MW (repetition rate=14 Hz, RF pulse width close to 3.6 milliseconds). The CEA Saclay is in charge of the design, the manufacturing, the preparation and the conditioning of these power couplers. In this paper, after a general presentation of the power couplers used in the ESS LINAC and their characteristics, we give some détails about the manufacturing and then we describe the different steps of the preparation (cleaning), the assembly of the couplers on the coupling box in cleanroom, the baking of the couplers and the conditioning procedure. Finally, the experimental results obtained in travelling and standing waves on the first pairs of couplers will be shown