August 28, 2023 to September 1, 2023
University of Vienna
Europe/Vienna timezone

The LEGEND-200 Liquid Argon Instrumentation: From a simple veto to a full-fledged detector

Aug 28, 2023, 6:30 PM
2h 30m
University of Vienna

University of Vienna

Universitätsring 1 A-1010 Vienna, Austria
Poster Neutrino physics and astrophysics Poster session


Rosanna Deckert (Technical University of Munich)


LEGEND-200 at LNGS is an experiment designed to search for neutrinoless double beta decay of Ge-76 by operating up to 200 kg of enriched Ge-detectors in liquid argon (LAr). To achieve ultra-low backgrounds, the LAr is instrumented to detect scintillation light emitted upon interactions with ionizing radiation, thus tagging and rejecting backgrounds. The LAr scintillation light is detected with wavelength-shifting fibers coupled to SiPM arrays. We demonstrate the high photoelectron (p.e.) resolution and low noise level of the SiPM signals. We also present the results of special calibration runs performed to determine the p.e. yield and background suppression factors. Maximized geometrical coverage and wavelength conversion efficiency result in a high p.e. yield, which in turn enables effective particle discrimination. We illustrate the suppression performance using K-lines and Ra–226 calibration data. Furthermore, we present the additional LAr DAQ trigger which allows the investigation of time-correlated backgrounds, such as BiPo-214 and muon-induced neutron captures on Ar-40. This, together with the particle discrimination capability, elevates the LAr instrumentation from a simple veto to a full-fledged detector.

This work is supported by: German MPG, BMBF, DFG; Italian INFN; Polish NCN, MNiSW; Czech MEYS; Slovak SRDA; European ERC, Horizon programs; Swiss SNF; UK STFC; U.S. DOE, NSF, LANL, ORNL, LBNL LDRD programs; Russian RFBR; Canadian NSERC, CFI; LNGS and SURF facilities.

Submitted on behalf of a Collaboration? Yes

Primary author

Rosanna Deckert (Technical University of Munich)


Andreas Leonhardt (Technical University of Munich) Christoph Vogl (Technical University of Munich) Daniya Zinatulina (Joint Institute for Nuclear Research) Diego Tagnani (Roma Tre University) Egor Shevchik (Joint Institute for Nuclear Research) Gabriela Araujo (University of Zurich) Giuseppe Salamanna (Roma Tre University) Igor Abritta (Roma Tre University) Konstantin Gusev (Joint Institute for Nuclear Research, Technical University of Munich) Laszlo Papp (Technical University of Munich) Laura Baudis (University of Zurich) Maria Fomina (Joint Institute for Nuclear Research) Mario Schwarz (Technical University of Munich) Nadya Rumyantseva (Joint Institute for Nuclear Research) Nina Burlac (Roma Tre University) Patrick Krause (Technical University of Munich) Stefan Schönert (Technical University of Munich) Valerio D’Andrea (Roma Tre University)

Presentation materials