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arXiv · 2107.03669

Radioactivity control strategy for the JUNO detector

JUNO collaboration·Angel Abusleme·Thomas Adam·Shakeel Ahmad·Rizwan Ahmed·Sebastiano Aiello·Muhammad Akram·Fengpeng An·Qi An·Giuseppe Andronico·Nikolay Anfimov·Vito Antonelli·Tatiana Antoshkina·Burin Asavapibhop·João Pedro Athayde Marcondes de André·Didier Auguste·Andrej Babic·Wander Baldini·Andrea Barresi·Davide Basilico·Eric Baussan·Marco Bellato·Antonio Bergnoli·Thilo Birkenfeld·Sylvie Blin·David Blum·Simon Blyth·Anastasia Bolshakova·Mathieu Bongrand·Clément Bordereau·Dominique Breton·Augusto Brigatti·Riccardo Brugnera·Riccardo Bruno·Antonio Budano·Mario Buscemi·Jose Busto·Ilya Butorov·Anatael Cabrera·Hao Cai·Xiao Cai·Yanke Cai·Zhiyan Cai·Antonio Cammi·Agustin Campeny·Chuanya Cao·Guofu Cao·Jun Cao·Rossella Caruso·Cédric Cerna·Jinfan Chang·Yun Chang·Pingping Chen·Po-An Chen·Shaomin Chen·Xurong Chen·Yi-Wen Chen·Yixue Chen·Yu Chen·Zhang Chen·Jie Cheng·Yaping Cheng·Alexey Chetverikov·Davide Chiesa·Pietro Chimenti·Artem Chukanov·Gérard Claverie·Catia Clementi·Barbara Clerbaux·Selma Conforti Di Lorenzo·Daniele Corti·Oliviero Cremonesi·Flavio Dal Corso·Olivia Dalager·Christophe De La Taille·Jiawei Deng·Zhi Deng·Ziyan Deng·Wilfried Depnering·Marco Diaz·Xuefeng Ding·Yayun Ding·Bayu Dirgantara·Sergey Dmitrievsky·Tadeas Dohnal·Dmitry Dolzhikov·Georgy Donchenko·Jianmeng Dong·Evgeny Doroshkevich·Marcos Dracos·Frédéric Druillole·Shuxian Du·Stefano Dusini·Martin Dvorak·Timo Enqvist·Heike Enzmann·Andrea Fabbri·Lukas Fajt·Donghua Fan·Lei Fan

Abstract

JUNO is a massive liquid scintillator detector with a primary scientific goal of determining the neutrino mass ordering by studying the oscillated anti-neutrino flux coming from two nuclear power plants at 53 km distance. The expected signal anti-neutrino interaction rate is only 60 counts per day, therefore a careful control of the background sources due to radioactivity is critical. In particular, natural radioactivity present in all materials and in the environment represents a serious issue that could impair the sensitivity of the experiment if appropriate countermeasures were not foreseen. In this paper we discuss the background reduction strategies undertaken by the JUNO collaboration to reduce at minimum the impact of natural radioactivity. We describe our efforts for an optimized experimental design, a careful material screening and accurate detector production handling, and a constant control of the expected results through a meticulous Monte Carlo simulation program. We show that all these actions should allow us to keep the background count rate safely below the target value of 10 Hz in the default fiducial volume, above an energy threshold of 0.7 MeV.

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JUNO collaboration, Angel Abusleme, Thomas Adam, Shakeel Ahmad, Rizwan Ahmed, Sebastiano Aiello, Muhammad Akram, Fengpeng An, Qi An, Giuseppe Andronico, Nikolay Anfimov, Vito Antonelli, Tatiana Antoshkina, Burin Asavapibhop, João Pedro Athayde Marcondes de André, Didier Auguste, Andrej Babic, Wander Baldini, Andrea Barresi, Davide Basilico, Eric Baussan, Marco Bellato, Antonio Bergnoli, Thilo Birkenfeld, Sylvie Blin, David Blum, Simon Blyth, Anastasia Bolshakova, Mathieu Bongrand, Clément Bordereau, Dominique Breton, Augusto Brigatti, Riccardo Brugnera, Riccardo Bruno, Antonio Budano, Mario Buscemi, Jose Busto, Ilya Butorov, Anatael Cabrera, Hao Cai, Xiao Cai, Yanke Cai, Zhiyan Cai, Antonio Cammi, Agustin Campeny, Chuanya Cao, Guofu Cao, Jun Cao, Rossella Caruso, Cédric Cerna, Jinfan Chang, Yun Chang, Pingping Chen, Po-An Chen, Shaomin Chen, Xurong Chen, Yi-Wen Chen, Yixue Chen, Yu Chen, Zhang Chen, Jie Cheng, Yaping Cheng, Alexey Chetverikov, Davide Chiesa, Pietro Chimenti, Artem Chukanov, Gérard Claverie, Catia Clementi, Barbara Clerbaux, Selma Conforti Di Lorenzo, Daniele Corti, Oliviero Cremonesi, Flavio Dal Corso, Olivia Dalager, Christophe De La Taille, Jiawei Deng, Zhi Deng, Ziyan Deng, Wilfried Depnering, Marco Diaz, Xuefeng Ding, Yayun Ding, Bayu Dirgantara, Sergey Dmitrievsky, Tadeas Dohnal, Dmitry Dolzhikov, Georgy Donchenko, Jianmeng Dong, Evgeny Doroshkevich, Marcos Dracos, Frédéric Druillole, Shuxian Du, Stefano Dusini, Martin Dvorak, Timo Enqvist, Heike Enzmann, Andrea Fabbri, Lukas Fajt, Donghua Fan, Lei Fan. 2021-07-08. Radioactivity control strategy for the JUNO detector. https://doi.org/10.1007/jhep11(2021)102

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