The Germanium Detector Array (GERDA) is a low background experiment at the Laboratori Nazionali del Gran Sasso (LNGS) of the INFN designed to search for the rare neutrinoless double beta decay (0 nu beta beta) of Ge-76. In its first phase, high purity germanium diodes inherited from the former Heidelberg-Moscow and IGEX experiments are operated "bare" and immersed in liquid argon, with an overall background environment of 10(-2) cts/(keV.kg.yr), a factor of ten better than its predecessors. Measurements on two-neutrino double beta decay (2 nu beta beta) giving T-1/2(2 nu) = (1.88 +/- 0.10) x 10(21) yr and recently published background model and pulse shape performances of the detectors are discussed in the paper. A new result on 0 nu beta beta been recently published with a half-life limit on 0 nu beta beta decay T-1/2(0 nu) > 2.1 x 10(25) yr (90% C.L.). A second phase of the experiment is scheduled to start during the year 2014, after a major upgrade shutdown. Thanks to the increased detector mass with new designed diodes and to the introduction of liquid argon instrumentation techniques, the experiment aims to reduce further the expected background to about 10(-3) cts/(keV.kg.yr) and to improve the 0 nu beta beta sensitivity to about T-1/2(0 nu) > 1.5 x 10(26) yr (90% C.L.).
Status of the GERDA Experiment at the Laboratori Nazionali del Gran Sasso
BRUGNERA, RICCARDO;GARFAGNINI, ALBERTO
2013
Abstract
The Germanium Detector Array (GERDA) is a low background experiment at the Laboratori Nazionali del Gran Sasso (LNGS) of the INFN designed to search for the rare neutrinoless double beta decay (0 nu beta beta) of Ge-76. In its first phase, high purity germanium diodes inherited from the former Heidelberg-Moscow and IGEX experiments are operated "bare" and immersed in liquid argon, with an overall background environment of 10(-2) cts/(keV.kg.yr), a factor of ten better than its predecessors. Measurements on two-neutrino double beta decay (2 nu beta beta) giving T-1/2(2 nu) = (1.88 +/- 0.10) x 10(21) yr and recently published background model and pulse shape performances of the detectors are discussed in the paper. A new result on 0 nu beta beta been recently published with a half-life limit on 0 nu beta beta decay T-1/2(0 nu) > 2.1 x 10(25) yr (90% C.L.). A second phase of the experiment is scheduled to start during the year 2014, after a major upgrade shutdown. Thanks to the increased detector mass with new designed diodes and to the introduction of liquid argon instrumentation techniques, the experiment aims to reduce further the expected background to about 10(-3) cts/(keV.kg.yr) and to improve the 0 nu beta beta sensitivity to about T-1/2(0 nu) > 1.5 x 10(26) yr (90% C.L.).
Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
