Underwater Photometry System of the SNO+ Experiment

Abstract

The SNO+ experiment is a large-scale liquid scintillator-based experiment, adapting the Sudbury Neutrino Observatory (SNO) detector located at SNOLAB, Canada. The main physics goal is to investigate the Majorana nature of neutrinos through the search for the neutrinoless double-beta decay of 130Te. The camera system of SNO+ is designed to photograph calibration sources and triangulate their locations with an accuracy of a couple of centimeters. This will lead to better calibrations and more accurate physics measurements in SNO+. The camera system, when operated in a special mode with underwater lights turned on, also allows monitoring of the physical state of the detector. The optical calibration source was deployed in the water filled SNO+ detector in the summer of 2017. Pictures of the deployed source were taken using the camera system while the underwater lights were turned on. The triangulation analysis of the pictures gave us an opportunity to test the position accuracy of the deployed source in SNO+ using the camera system.