Speaker
Description
The work presents calculations of the neutrino-nuclear reaction cross-sections using the
example of the nucleus ๐บ๐'( (๐บ๐'( ๐, ๐ ๐ด๐ '( ). In the structure of the nucleus, not only
discrete, but also continuous states formed due to the collective interaction of nucleons were
distinguished. In particular, the contribution of the Giant Gamow-Teller resonance and so-called
pygmy resonances in the capture rate of solar neutrinos was estimated (an increase of 25% to
50%, depending on the quenching parameter used).
Based on the obtained capture rate, a Monte Carlo simulation of the subsequent beta
decay of the nucleus ๐ด๐ '( (๐ด๐ '( โ ๐๐'( + ๐2 + ๐ + ๐๐พ) was carried out for germanium
detectors in the GERDA experiment. Thus, the contribution of the background component due
to solar neutrinos was estimated, which, due to the small cross-sections of neutrino-nuclear
reactions, is practically unremovable, imposing confines on the sensitivity limit of the setup.
A similar assessment can be made for the upcoming LEGEND experiment taking into
account its geometry. Preliminary results suggest that BI of solar neutrinos are 1-2 orders of
magnitude lower than the predicted accuracy of the LEGEND experiment.
