Meteoric 10 Be in aerosol filters in the city of Seville.

Cosmogenic radionuclides in the one-million-year half-life range, like 10 Be, find application fields in several Sciences. They are powerful tools in Geology and Geochronology, as they are very important tracers on the Earth, being utilized as chronometer. Meteoric 10 Be (T1/2  = 1.39 × 106  y) associated to aerosols can be used as a tracer of atmospheric processes and specifically as indicators of the cosmogenic interactions in lower Stratosphere, upper Troposphere, the air exchange between both and deposition processes on the Earth surface. The applications of 10 Be are even more relevant when combined with other radionuclides such as 26 Al. In order to provide new data about concentration 10 Be in this type of samples, the first atmospheric air filters in Spain have been analysed. Values around 104  at/m3 (atoms per cubic meter of air) for 10 Be have been obtained. Due to the location and the features of the sampling site (urban area, at sea level and mid latitude), a new radiochemical procedure was designed and developed in our laboratory for the Accelerator Mass Spectrometry (AMS) measurement of 10 Be in this kind of samples. The samples were measured in SARA, the 1 MV AMS system at Centro Nacional de Aceleradores (CNA).