Münster 2017 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HK: Fachverband Physik der Hadronen und Kerne

HK 14: Astroparticle Physics I

HK 14.1: Group Report

Tuesday, March 28, 2017, 11:00–11:30, F 33

First results of Gerda Phase II — •Anne Wegmann for the GERDA collaboration — Max-Planck-Institut für Kernphysik, Heidelberg

The Gerda experiment is searching for neutrinoless double beta (0νββ) decay of ⁷⁶Ge. Gerda operates bare Germanium detectors in liquid argon, that are enriched in the ββ isotope. Phase II of the experiment combines for the first time the excellent properties of semiconductor Germanium detectors with an active background suppression technique based on the simultaneous detection of liquid argon scintillation light by photomultiplier tubes and silicon photomultipliers coupled to scintillating fibers (LAr veto).

This talk outlines the Phase II upgrade with special emphasis on background rejection techniques and focusses on the first results of Phase II. Exhibiting the world-best background index (if normalized to the narrow energy-signal region of Germanium detectors), a limit on the 0νββ-decay half-life of 5.3 · 10²⁵ yr at 90% C.L. could be set based on an exposure of only 34.4 kg·yr. With an ultimate exposure of 100 kg·yr this will allow for a 0νββ-decay half-life sensitivity of the Gerda Phase II experiment of 10²⁶ yr.