New technique of ion identification in Accelerator Mass Spectrometry using low-pressure TPC with GEM readout

Abstract We have developed and successfully tested a low-pressure Time Projection Chamber (TPC) with Gas Electron Multiplier (GEM) readout for Accelerator Mass Spectrometry (AMS). AMS facility in Novosibirsk has problem of separating isobar ions different chemical elements that the same atomic mass. The typical example is radioactive isotopes 10 Be B are used to date geological objects at time scale ten million years. To solve this problem, new ion identification technique, namely based on measuring both track ranges energies TPCs GEM readout, been developed. This technique proposed be applied dating objects, geochronology Cenozoic era. In work, we larger version TPC dedicated thin silicon nitride window an efficient passage ions. characteristics were studied isobutane low pressures using alpha particle sources. addition, use instead THGEM shown substantially improve energy resolution nominal pressure (50 torr). Using these results SRIM code simulations, it isobaric boron beryllium can effectively separated AMS, providing will near future.