Background reduction in the SNO+ experiment

Journal Article · Mon Aug 17 00:00:00 EDT 2015 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4928004· OSTI ID:22488721

Segui, L. ^[1]

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1. University of Oxford, Denys Wilkinson Building, Keble Road, OX1 Oxford (United Kingdom)

SNO+ is a large multi-purpose liquid scintillator experiment, which first aim is to detect the neutrinoless double beta decay of {sup 130}Te. It is placed at SNOLAB, at 6000 m.w.e. and it is based on the SNO infrastructure. SNO+ will contain approximately 780 tonnes of liquid scintillator, loaded with {sup 130}Te inside an acrylic vessel (AV) with an external volume of ultra pure water to reduce the external backgrounds. Light produced in the scintillator by the interaction of particles will be detected with about 9,000 photomultiplier’s. For the neutrinoless double beta decay phase, due to its the extremely low rate expected, the control, knowledge and reduction of the background is essential. Moreover, it will also benefit other phases of the experiment focused on the study of solar neutrinos, nucleon decay, geoneutrinos and supernovae. In order to reduce the internal background level, a novel purification technique for tellurium loaded scintillators has been developed by the collaboration that reduces the U/Th concentration and several cosmic-activated isotopes by at least a factor 10{sup 2} -10{sup 3} in a single pass. In addition, different rejection techniques have been developed for the remaining internal backgrounds based on Monte-Carlo simulations. In this work, the scintillator purification technique and the levels obtained with it will be discussed. Furthermore, an overview of the different backgrounds for the double-beta phase will be presented, highlighting some of the techniques developed to reject the remained decays based on their expected timing differences.

• OSTI ID: 22488721
• Journal Information: AIP Conference Proceedings, Vol. 1672, Issue 1; Conference: LRT 2015: 5. international workshop in low radioactivity techniques, Seattle, WA (United States), 18-20 Mar 2015; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
COMPUTERIZED SIMULATION
CONCENTRATION RATIO
DOUBLE BETA DECAY
LIQUID SCINTILLATION DETECTORS
MONTE CARLO METHOD
NEUTRINO DETECTION
NUCLEONS
PHOSPHORS
PURIFICATION
SOLAR NEUTRINOS
SUDBURY NEUTRINO OBSERVATORY
SUPERNOVAE
TELLURIUM
TELLURIUM 130
VISIBLE RADIATION
WATER