Recent advances in studies of meteorites using cosmogenic radionuclides

Abstract

The use of accelerator mass spectrometry (AMS) to measure cosmogenic radionuclides in meteorites has greatly enabled studies of cosmic-ray exposure histories. The high sensitivity of AMS has allowed measurements of samples that are very small or have very low activities. AMS measurements have much better accuracy and precision than usually possible with decay counting. AMS allows the routine measurements of many long-lived radionuclides, including some with half-lives not regularly measured previously or some made by neutron-capture reactions (such as 36Cl, 41Ca and 59Ni). These advancements have enabled many meteorite studies that previously were not often done, such as terrestrial ages. All aspects of a meteorite's cosmic-ray exposure history, its ages and geometries, now can be better studied.