The Korean Physical Society 06130 22, Teheran-ro 7-gil, Gangnam-gu, Seoul, Republic of Korea 610 Representation : Suk Lyun HONG TEL: 02-556-4737 FAX: 02-554-1643 E-mail : webmaster@kps.or.kr Copyright(C) KPS, All rights reserved.
May 30, 2022 to June 4, 2022
Virtual Seoul
Asia/Seoul timezone

The LEGEND-200 LAr instrumentation: from design to commissioning

Not scheduled
5m
Virtual Seoul

Virtual Seoul

Poster Neutrinoless double beta decay Poster

Speakers

Egor Shevchik (Joint Institute for Nuclear Research, Dubna, Russia.) Nina Burlac (University and INFN of Roma Tre, Rome, Italy.)

Description

The Liquid Argon (LAr) instrumentation of the neutrinoless double-beta decay experiment LEGEND-200 builds on its precursor [1] operated in the completed GERDA experiment. Thanks to its efficient background recognition capabilities, it was pivotal to search for neutrinoless double-beta decays of $^{76}$Ge quasi-free of background events [2]. An improved version has been developed and is deployed in LEGEND-200 at the Laboratori Nazionali del Gran Sasso. The low-background LAr instrumentation detects the argon scintillation light created by energy depositions in the liquid argon that accompanies energy depositions in the high-purity germanium detectors. Such background events originate from $\alpha$, $ \beta$, $ \gamma$ or neutron interactions, originating from primordial, anthropogenic radioisotopes or cosmogenic produced unstable isotopes. They must be discriminated from neutrinoless double beta decay signals, which have energy deposition inside the germanium detectors and no energy deposition in the liquid argon. The LAr instrumentation consists of two concentric curtains of WaveLength Shifting (WLS) fibers, realized by evaporation of the fibers with TetraPhenyl Butadiene (TPB) and read out with arrays of Silicon PhotoMultipliers (SiPM). The TPB first shifts the LAr scintillation light from 128 nm vacuum ultraviolet to blue light. Subsequently, the blue light is absorbed inside the fibers and shifted to the green, and guided by total internal reflection to the low-background SiPM arrays mounted on both ends of the fiber module. The electrical signals are transmitted via differential transmission lines and amplified outside the liquid argon. The full traces are recorded with a flash-ADC system and stored for offline analysis. Transparent, TPB coated nylon shrouds complement the LAr instrumentation surrounding germanium detector strings and a reflecting and WaveLength Shifting Reflector (WLSR) of cylinder geometry enclosing the germanium and fiber arrays. The poster will cover the phases of the LAr instrumentation: from the design and its requirements to the first analysis of commissioning data.

[1] Optical fiber read-out for liquid argon scintillation light, J. Janicskó Csáthy, T.Bode, J. Kratz, S. Schönert, Ch. Wiesinger, https://doi.org/10.48550/arXiv.1606.04254.
[2] Final Results of GERDA on the Search for Neutrinoless Double-$ \beta $ Decay, GERDA Collaboration M. Agostini et. al., PRL 125, 252502 (2020).

Collaboration LEGEND Collaboration

Primary authors

Egor Shevchik (Joint Institute for Nuclear Research, Dubna, Russia.) Nina Burlac (University and INFN of Roma Tre, Rome, Italy.)

Co-authors

Alexey Lubashevskiy (Joint Institute for Nuclear Research, Dubna, Russia.) Daniya Zinatulina (Joint Institute for Nuclear Research, Dubna, Russia.) Diego Tagnani (University and INFN of Roma Tre, Rome, Italy.) Elisabetta Bossio (Technische Universität München, Germany.) Elizabeth Mondragon (Technische Universität München, Germany.) Francesco Paissan (University and INFN of Roma Tre, Rome, Italy.) Gabriela Araujo (Universität Zürich, Switzerland.) Giuseppe Salamanna (University and INFN of Roma Tre, Rome, Italy.) Igor Abritta Costa (University and INFN of Roma Tre, Rome, Italy.) Konstantin Gusev (Joint Institute for Nuclear Research, Dubna, Russia.) Laszlo Papp (Technische Universität München, Germany.) Laura Baudis (Universität Zürich, Switzerland.) Maria Fomina (Joint Institute for Nuclear Research, Dubna, Russia.) Mario Schwarz (Technische Universität München, Germany. ) Nadya Rumyantseva (Joint Institute for Nuclear Research, Dubna, Russia.) Patrick Krause (Technische Universität München, Germany.) Rosanna Deckert ( Technische Universität München, Germany) Stefan Schönert (Technische Universität München, Germany. )

Presentation materials