The LED and fiber based calibration system for the photomultiplier array of SNO+

[摘要] A new external LED/fiber light injection calibration system was designed for the calibration and monitoring of the photomultiplier array of the SNO+ experiment at SNOLAB. The goal of the calibration system is to allow an accurate and regular measurement of the photomultiplier array's performance, while minimizing the risk of radioactivity ingress. The choice in SNO+ was to use a set of optical fiber cables to convey into the detector the light pulses produced by external LEDs. The quality control was carried out using a modified test bench that was used in QC of optical fibers for TileCal/ATLAS. The optical fibers were characterized for transmission, timing and angular dispersions. This article describes the setups used for the characterization and quality control of the system based on LEDs and optical fibers and their results.

[发布机构] Laboratório de Instrumentação e Física Experimental de Partículas, Av. Elias Garcia 14, 1, Lisboa; 1000-149, Portugal^1;Laboratório de Instrumentação e Física Experimental de Partículas, Departamento de Física, Universidade de Coimbra, Coimbra; 3004-516, Portugal^2;School of Physics and Astronomy, University of Leeds, Leeds; LS2 9JT, United Kingdom^3;Department of Physics and Astronomy, University of Sussex, Falmer Campus, Brighton; BN1 9QH, United Kingdom^4;Department of Physics, Oxford University, Denys Wilkinson Building, Keble Road, Oxford; OX1 3RH, United Kingdom^5;Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley; CA; 94720, United States^6;Department of Physics and Astronomy, Laurentian University, Sudbury; ON; 2C6, Canada^7;Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Edificio C8, Lisboa; 1749-016, Portugal^8;Department of Physics, University of Liverpool, Liverpool; L69 7ZE, United Kingdom; (10) Centro de Física Nuclear, Universidade de Lisboa, Av. Prof. Gama Pinto, Lisboa 2; 1649-003, Portugal; (11) Queen's University, Physics Department, Kingston; ON; 3N6, Canada; (12) School of Physics and Astronomy, Queen Mary, University of London, 327 Mile End Road, London; E1 4NS, United Kingdom^9

[关键词] Angular dispersions;Calibration system;Light injection;Light pulse;Photomultiplier arrays;Test benches;TileCal