Neutrinos? GERDA and the Neurtinoless Double Beta-Decay

by Dr Bela Majorovits (MPP)

Tuesday 6 Mar 2012, 17:15 → 18:15 Europe/Berlin

MPP Auditorium

Observation of neutrinoless double beta (0vbb) -decay could answer the question whether Neutrinos are their own anti-particles or not and could yield information on the absolute mass scale of neutrinos. The most stringent half-life limit for 76Ge is T1/2>1.9 1025 years. This can be translated to the lowest present limit for the effective Majorana neutrino mass of <m> < 0.3eV. Part of the Heidelberg-Moscow collaboration claims to have observed 0vbb-decay in 76Ge with T1/2=1.2 1025 years, however this result is controversial. A short motivation for 0vbb-decay searches will be given. The principle of 0vbb-searches utilizing High Purity Germanium enriched in the isotope 76Ge detectors will be introduced. The general design features of the GERDA experiment - designed to confirm or refute the claim within one year of measurement – will be shown. Results from the GERDA commissioning runs and the status of GERDA data taking with enriched detectors will be discussed. Plans and status of preparations of the second phase of the GERDA experiment will be shown.