First Evidence for Neutrinoless Double Beta Decay from the Heidelberg-Moscow Experiment
Abstract
Double beta decay is one of the rarest nuclear decay modes and is under investigation already for more than sixty years. The neutrinoless mode is of particular interest since it would violate lepton number and its occurrence would determine the neutrino to be a Majorana particle. Double beta decay experiments are indispensable to solve the structure of the neutrino mass matrix. They further probe, complementary to high energy colliders, other fields of beyond standard model physics. The present experimental status is reviewed including the recent evidence for the neutrinoless decay mode from the Heidelberg-Moscow experiment, which yields a half-life of T_1/2= 1.5 (+16.8, -0.7) x 10^25 y (95% c.l.). This corresponds to an effective neutrino mass of 0.39 (+0.45, -0.34) eV (95% c.l.), assuming that contributions to neutrinoless double beta decay from processes other than exchange of Majorana neutrinos are negligible. Consequences and future perspectives are discussed.
- Publication:
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APS April Meeting Abstracts
- Pub Date:
- April 2003
- Bibcode:
- 2003APS..APR.B7002K