KARLSRUHE-CERN SUPERCONDUCTING RF SEPARATOR

In December 1977 the superconducting rf separator developed and constructed at KfK, Karlsruhe was operated for the first time in a counter beam at CERN. The separator uses two disk loaded niobium deflectors of 2.74 m length with 104 cells which are operated in a π 2-mode at 2865 MHz. It is connected to the large 300 W refrigerator of CERN allowing an operation temperature of 1.8 K. The design, fabrication and surface treatments of the superconducting deflectors are briefly described and experimental results are reviewed. Quality factors above 2 × 109 and deflection fields of 1.2 and 1.4 MV/m resp. (corresponding to peak magnetic fields of 18.5 and 22.5 resp.) have been obtained. A brief description of the rf components, rf regulation systems, vacuum systems and cryostats is given. Since March 1978 the separator is used in physics experiments and has by now accumulated a total of more than 3000 h of operation. No degradation of deflector performances has been observed. Separation of K between 8 and 26 GeV/c and of p between 3.3 and 37 GeV/c has been obtained. Enrichments of wanted particles with respect to an unseparated beam well above the anticipated factor 10 have been reached. © 1979.