Accelerator mass spectrometry: New applications

Accelerator mass spectrometry (AMS) is an ultra-sensitive detecting technique that is able to measure minute quantities of long-lived radioisotopes with high accuracy in samples of only a few milligrams of sample size. From the great variety of investigations in connection with the AMS method, some examples of new AMS applications are discussed. In case of 14C, problems of absolute age dating and calibration of radiocarbon dates are pointed out. Applications of other cosmogenic radioisotopes are discussed in connection with tracer studies. Of particular interest are ice cores from the polar regions that contain radioisotope records extending over several hundred thousand years. Measurements of 10Be and 36Cl concentrations in these ice cores are related to solar activity and atmospheric transport processes. A new field of AMS application deals with cosmic radioisotope production in lithosphere. Here an example of erosion measurements of a limestone surface from Vue des Alpes (Switzerland) is shown. Cosmogenic radioisotopes in extraterrestrial materials provide information on cosmic radiation. The detailed knowledge of all important nuclear reactions is necessary for the modelling of irradiation profiles in meteorites.