Borexino is a liquid scintillator detector situated underground in the Laboratori Nazionali del Gran Sasso in Italy. Its physics program evolves around the study of solar and geo-neutrinos. By now, Borexino has measured neutrinos from the fusion processes in the pp chain and CNO cycle. Especially for the detection of pep and CNO neutrinos, an important background is formed by the cosmogenic radio-isotope 11C that is produced by muon spallation of 12C nuclei in the scintillator. Given the comparatively long life time (30 mins) and high rate (30 cpd and 100 ton), dedicated veto strategies had to be developed to permit the detection of pep and CNO neutrinos. The present contribution presents two veto methods. One is the well-established Three-Fold Coincidence (TFC) technique that relies on time and space correlation of muons, spallation neutrons, and radioactive 11C decays; it has been used in different implementations in all former Borexino analyses. In addition, a newly devised algorithm searching for time-correlated bursts of 11C events will be presented, highlighting as well the potential gain from a combined application with the TFC technique.
|Journal of Physics: Conference Series
|Published - Feb 21 2022
|17th International Conference on Topics in Astroparticle and Underground Physics, TAUP 2021 - Virtual, Online
Duration: Aug 26 2021 → Sep 3 2021
All Science Journal Classification (ASJC) codes
- General Physics and Astronomy