Commissioning of the COBRA extended demonstrator at the LNGS

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung


  • J. H. Arling - , Technische Universität (TU) Dortmund, Helmholtz-Zentrum Dresden-Rossendorf (Autor:in)
  • L. Bodenstein-Dresler - , Technische Universität (TU) Dortmund (Autor:in)
  • Y. Chu - , Professur für Kernphysik, Technische Universität Dresden (Erstautor:in)
  • D. Gehre - , Institut für Kern- und Teilchenphysik (IKTP), Technische Universität Dresden (Autor:in)
  • C. Goessling - , Technische Universität (TU) Dortmund (Autor:in)
  • C. Herrmann - , Technische Universität (TU) Dortmund (Autor:in)
  • R. Hodak - , Czech Technical University in Prague (Autor:in)
  • K. Kroeninger - , Technische Universität (TU) Dortmund (Autor:in)
  • M. Macko - , Czech Technical University in Prague (Autor:in)
  • M. Petro - , Czech Technical University in Prague (Autor:in)
  • K. Rohatsch - , Professur für Strahlenphysik (gB/HZDR), Technische Universität Dresden (Autor:in)
  • E. Rukhadze - , Czech Technical University in Prague (Autor:in)
  • I Stekl - , Czech Technical University in Prague (Autor:in)
  • J. Tebruegge - , Technische Universität (TU) Dortmund (Autor:in)
  • R. Temminghoff - , Technische Universität (TU) Dortmund (Autor:in)
  • J. Volkmer - , Professur für Kernphysik, Technische Universität Dresden (Autor:in)
  • S. Zatschler - , Professur für Kernphysik, Technische Universität Dresden (Autor:in)
  • K. Zuber - , Professur für Kernphysik, Technische Universität Dresden (Autor:in)


The COBRA experiment aims to search for the neutrinoless double beta decay by using CdZnTe (CZT) semiconductor detectors. A demonstrator setup, comprising 64 CZT detectors with a volume of 1 cm(3) each, was operated at the underground Laboratori Nazionali del Gran Sasso (LNGS). The COBRA collaboration has recently upgraded the demonstrator to the extended demonstrator (XDEM). An array of nine large volume 2 x 2 x 1.5 cm(3) CZT room temperature semiconductor detectors with a total mass of 315.1 g was installed to increase the half-life sensitivity. The innovative detector design and improved detector handling procedures during commissioning allow for an improved energy resolution of the detectors while the most prominent backgrounds that were identified during the demonstrator operation are expected to be reduced significantly. This article gives an overview of the new hardware components and the background present in the setup. Furthermore, the energy and position reconstruction is described in detail, including the correction of electron trapping. All functional detectors demonstrated a good stability in the long-term operation. The analysis of the commissioning data confirms the excellent energy resolution of the detectors, as well as an improvement of the background level by more than one order of magnitude compared to the previous demonstrator setup.


FachzeitschriftNuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Frühes Online-DatumJuni 2021
PublikationsstatusVeröffentlicht - 11 Sept. 2021

Externe IDs

Scopus 85108009539



  • CdZnTe semiconductor detector, Double beta decay, Low background, Quad coplanar grid