Navigation auf uzh.ch

Suche

Physik-Institut Group of Laura Baudis

GERDA sets a new sensitivity record for the neutrinoless double beta decay

One of the highlights of this year's Neutrino conference were new results from the GERDA experiment: with a large data release, GERDA has doubled its exposure, for a total of 82.4 kg years.

Improvements in background suppression techniques have brought down the background expectation to 0.1 events per exposure in the energy region of interest of the decay. GERDA is now the most sensitive experiment in the field, with a  half-life sensitivity of 1026 yr for the neutrinoless double beta decay of 76Ge.

No signal was detected yet, and an upper limit on the half-life could be set: a 76Ge atom takes on average longer than ten quadrillion times the age of the universe to decay via this rare process which is not allowed in the Standard Model of particle physics and would violate lepton number conservation by ΔL = 2.