The origin of matter and the origin of mass are fundamental questions in physics.
One of the keys to understand these problems is the study of the neutrino mass and its origin. The Majorana nature of the neutrino may explain the matter-antimatter asymmetry that causes the excess of matter in our Universe. Double beta decay is believed to be the most promising phenomena to prove the Majorana nature of the neutrino. Double beta decay is, however, a very rare event. We may observe a few events in a year with hundreds of source nuclei. A very low background environment and a very high detection efficiency is necessary to observe such rare events.
We are developing advanced radiation detectors to explore this physics in the Super NEMO collaboration. Super NEMO, which is an international collaboration, is a project for exploring the double beta decay in the mass region of a few hundreds meV.
Assuming charge symmetry of the nuclear interaction, ISOSPIN is a good quantum number. Then isospin symmetry structure is expected among the nuclei with the same mass number A (isomers) and isobaric analogous states can exist in isomers. It should be noted that various transitions between different combinations of analogous states are also analogous. We are studying nuclear structures through isospin symmetry using charge exchange reactions such as (He3,t) reactions.
SuperNEMO detector for
double beta decay measurement.
SuperNEMO project is the next-generation
ββ0ν Tracko-Calo experiment
with a sensitivity on <mν> ≤ 50meV
SuperNEMO is an international collaboration.
France, UK, Spain, Russia, Czech,
Ukraine, USA, Japan