RECENT DEVELOPMENTS FOR THE HESR STOCHASTIC COOLING SYSTEM

Two cooling systems will be installed in the HighEnergy Storage Ring (HESR) of the future international Facility for Antiproton and Ion Research (FAIR) [1] at the GSI in Darmstadt: an electron cooler (1.5-8 GeV/c) and a stochastic cooling system from 3.8 GeV/c up to the highest momentum of the HESR (15 GeV/c). Both coolers are mandatory for the operation of the HESR with the PANDA pellet target. The relative low aperture (89mm) of the HESR suggests fixed structures without a plunging system. An octagonal layout was chosen to increase the sensitivity of the electrodes. Two different types of electrodes were built and tested. We will report on the comparison of printed lambda/4 loops and new broadband slot couplers.