The CUORICINO ββ-decay detector is an array of 62 TeO2 bolometers;4 4 are 5 × 5 × 5-cm crystals made with natural tellurium (33.8% 130Te). There are 18, 3 × 3 × 6-cm crystals, 14 of which are made of natural tellurium, 2 are isotopically enriched to 75% in 130Te, and 2 are enriched to 82.3% in 128Te. The total mass of 130Te is ∼ 11 kg. The background rate is 0.23 ± 0.04 counts/keV/kg/yr in the energy interval 2480 to 2600 keV. During the cooling process, some of the wires became disconnected and only 32 of the large and 16 of the smaller crystals could be read out. The data presented here come from 29 of the 5 × 5 × 5-cm crystals containing 6.2 kg of 130Te. The new limit on the half-life is T 0ν 1/2 ≥ 5 × 1023 yr, corresponding to an effective Majorana mass of the electron neutrino mν between 0.42 and 2.05 eV, depending on the nuclear model used to analyze the data.
The CUORICINO 130Te beta-beta-DECAY EXPERIMENT AND A NEW LIMIT ON T0v1/2 beta-beta
GIULIANI, ANDREA ERNESTO GUIDO;PEDRETTI, MARISA;
2004-01-01
Abstract
The CUORICINO ββ-decay detector is an array of 62 TeO2 bolometers;4 4 are 5 × 5 × 5-cm crystals made with natural tellurium (33.8% 130Te). There are 18, 3 × 3 × 6-cm crystals, 14 of which are made of natural tellurium, 2 are isotopically enriched to 75% in 130Te, and 2 are enriched to 82.3% in 128Te. The total mass of 130Te is ∼ 11 kg. The background rate is 0.23 ± 0.04 counts/keV/kg/yr in the energy interval 2480 to 2600 keV. During the cooling process, some of the wires became disconnected and only 32 of the large and 16 of the smaller crystals could be read out. The data presented here come from 29 of the 5 × 5 × 5-cm crystals containing 6.2 kg of 130Te. The new limit on the half-life is T 0ν 1/2 ≥ 5 × 1023 yr, corresponding to an effective Majorana mass of the electron neutrino mν between 0.42 and 2.05 eV, depending on the nuclear model used to analyze the data.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.