Giuseppe Salamanna: Status and Prospects of LEGEND Experiment
by
https://zoom.us/j/97041428849
If neutrinos were the one (and only) instance of elementary particles of the Majorana type, they could undergo a hypothetical process violating lepton number, the so-called Neutrinoless double-beta decay (0νββ). If 0νββ indeed were observed, that would be enough to claim the Majorana nature of neutrinos.
Several experiments have been conceived which search for 0νββ in a handful of isotopes, baring a favourable energy-momentum configuration. A variety of
experimental techniques are being employed in the quest. So far the best statistical sensitivity on the half-life for the 0νββ process occurrence is of around 10^{26} yr and belongs to experiments employing $^76$Ge (germanium) both as source and as semi-conducting detector. It comes from an experiment called GERDA, based at the Italian underground Laboratori Nazionali del Gran Sasso (LNGS).
In this seminar I will focus on the child born of GERDA and its US counterpart, the "MAJORANA Demonstrator": LEGEND.
Using a two-stage approach with about 200 kg first and then 1000 kg of germanium diodes enriched in $^76$Ge, LEGEND aims to attain a sensitivity around $10^{28}$ yr in half-life, probing the inverted-ordering of the neutrino masses.
I will review the general concept and design of LEGEND; describe the detectors and their preliminary performance in the present LEGEND-200 phase, from a few months of commissioning at LNGS. I will also illustrate how the backgrounds can have a dramatic effect on the search; and in which way it can be mitigated, with some stress on the use of the liquid-argon detector. Finally, I will provide an expected timeline to get LEGEND-1000 up and running and the related R&D activities.
The seminar will be given in person in Niels Bohr, Schuster. For those connecting remotely please use:
https://zoom.us/j/97041428849
Meeting ID: 970 4142 8849
Passcode: 6275