Status of the Power Couplers for the ESS Elliptical Cavity Prototypes

Abstract

International audienceIn the frame of the European Spallation Source (ESS) project, a linear accelerator composed of a superconducting section is being developed. This accelerator owns two kinds of cavities called “medium beta cavity” (β=0.67) and “high beta cavity” (β= 0.86). These cavities are equipped with RF power couplers whose main characteristics are: fundamental frequency: 704.42MHz, peak RF power: 1.1MW, repetition rate: 14Hz, RF pulse width>3.1ms. These couplers are common to the two cavities. The CEA Saclay is responsible for the design, the manufacture, the preparation and the conditioning of the couplers used for the Elliptical Cavities Cryomodule Technological Demonstrators (ECCTD). This work is performed in collaboration with ESS and the IPNO. This paper describes the coupler architecture, its different components, the main characteristics and the specific features of its elements (RF performance, dissipated power, cooling, coupler box test for the conditioning). The status of the manufacture of each coupler part is also presented