Würzburg 2018 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

T: Fachverband Teilchenphysik

T 43: Neutrinophysik II

T 43.3: Gruppenbericht

Dienstag, 20. März 2018, 17:05–17:25, Z6 - SR 2.012

Status and prospects of the COBRA experiment — •Stefan Zatschler for the COBRA collaboration — TU Dresden, Institut für Kern- und Teilchenphysik, Germany

The COBRA experiment is dedicated to the search for the hypothesized neutrinoless double beta-decay (0νββ-decay). The observation of this lepton number violating process would prove the Majorana nature of neutrinos and shed first light on physics beyond the established Standard Model. The COBRA collaboration is currently operating a demonstrator array of 4×4×4 monolithic crystals at the underground facility LNGS (Italy). The detectors are made of CdZnTe, which is a commercially available semiconductor at room temperature. In 2018 a new detector module will be implemented to establish the COBRA extended demonstrator (COBRA XDEM). For this a new prototype of CdZnTe detectors with advanced veto capabilities has been developed and approved. In the transition phase the existing COBRA demonstrator was optimized for low-threshold operation to investigate the fourfold forbidden non-unique β-decay of ¹¹³Cd. The spectral shape of the electron momentum distribution of this highly forbidden decay is sensitive to the effective value of the axial vector coupling strength g_A in a nuclear medium. Such experimental input is urgently needed in the scientific discussion of quenching effects that might affect the half-life predictions for the 0νββ-decay. This talk will present the status of COBRA XDEM, the current and improved detector technology as well as the status of the recent physics analysis.

COBRA is funded by the German Research Foundation DFG.