%J Memorie della Societ? Astronomica Italiana %N 14 %K Sun: activity ? Meteoroids ? Cosmic rays ? Sun: magnetic fields ? Techniques: gamma spectroscopy ? Sunspots ? Interplanetary medium ? Solar-terrestrial relations %A Carla Taricco %A Narendra Bhandari %A Paolo Colombetti %A I. Mariani %A Neeharika Verma %A Gianna Vivaldo %D 2010 %L eprints2358 %X The study of long-term solar activity variations in the past requires the use of radioisotopic data planetary reservoirs. At the Laboratory of Monte dei Cappuccini in Torino (IFSI-Torino, INAF) for many years we have been studying radioisotopes in meteorites, because their production, which is related to galactic cosmic ray flux in the heliosphere, is anticorrelated with the heliospheric magnetic field variations. We have developed very sensitive gamma detection techniques, in particular to measure 44Ti activity in meteorites; due to its half-life (t1=2 = 59:2 years), this radioisotope is an ideal index to reveal the imprint of solar activity variations on the centennial scale. Recently we have improved the spectrometer by a new multiparametric acquisition system, which allows to extract efficiently the 44Ti peak from the natural background. %V Suppl. %I Societ? Astronomica Italiana %P 177-179 %T A multiparametric HPGe-Nal acquisition system for low gamma activity measurements of meteorites