CL-36 MEASUREMENTS AT THE ZURICH AMS FACILITY

During the past few years several improvements of the Cl-36 detection system at the Zurich AMS facility have been made. The high mass separation capability and the optimised detection system provide sufficient sensitivity to perform Cl-36 measurements at a beam energy of less than 50 MeV. Background ratios of less than 10(-15) can be achieved under routine operating conditions. A throughput of 50 samples per day makes it possible to contribute to projects where large numbers of samples are required. The main application of Cl-36 at Zurich is the analysis of Arctic ice cores. From the three different locations, Milcent station (70-degrees 18'N, 44-degrees 35'W), Dye-3 station (65-degrees 11'N, 43-degrees 49'W) and Summit (72-degrees 34'N, 37-degrees 38'W), ice cores have been investigated. The present status of these projects is discussed.