The Gerda experiment at the Laboratori Nazionali del Gran Sasso in Italy uses germanium detectors made from material with an enriched Ge-76 isotope fraction to search for neutrinoless double beta decay of this nucleus. Applying a blind analysis we find no signal after an exposure of 21.6 kg.yr and a background of about 0.01 cts/(keV.kg.yr). A half-life limit of T-1/20(v) > 2.1 . 10(25) yr (90% C.L.) is extracted. The previous claim of a signal for Ge-76 is excluded with 99% probability in a model independent way. (C) 2015 The Authors. Published by Elsevier B.V.
File in questo prodotto:
Non ci sono file associati a questo prodotto.