Abstract:
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.
