LEMA facility in the determination of meteoric ¹⁰Be

Full text: The National Laboratory of Mass Spectrometry (LEMA for its acronym in Spanish) is an AMS facility inaugurated in 2013. It is based on a 1 MV High Voltage Europe Engineering isotope separator. Since its foundation, LEMA has carried out numerous analyses in the study of ¹⁴C, which has been mainly used to date geological and archeological samples. More recently, a significant effort has been made to open new lines of research. The AMS system at LEMA has been optimized to measure the cosmogenic radionuclide ¹⁰Be. Several radiochemical procedures of extraction of this radionuclide have been analyzed and improved in different samples. ¹⁰Be is a cosmogenic radionuclide produced by spallation reactions between high-energy cosmic radiation and some atmosphere elements, mainly nitrogen and oxygen. Its long half-life (T1/2=1.39×106 y) makes it an element of great interest in environmental and geophysical sciences studies. The studies of meteoric ¹⁰Be have been applied extensively to many different systems in the last decades. Its study in rain waters, surface firns, ice cores, and particulate matter samples provides essential information about its production and distribution in the atmosphere. It can also be used as a tracer of climatic events. For example, meteoric ¹⁰Be associated with the aerosols can be used as a tracer of interactions in the lower Stratosphere, upper Troposphere, the air exchange between both atmospheric layers, and the deposition processes of Earth surface. The information obtained from the analysis of the meteoric ¹⁰Be production is a powerful tool to increase the knowledge about past environmental and climatic changes due to being able to be used as tracer operating over time scales up to 107 years. In this work, the preliminary results of the meteoric ¹⁰Be in particulate matter, rain, and snow samples, as well as the characterization of the process of extraction and measurement of this radioisotope with the AMS technique at the LEMA, Mexico facility, are presented.