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arXiv · 1812.01364

Calibration of photomultiplier using UVLED

Sungrae Im·Bokkyun Shin·Ikeda Daisuke·Stan Thomas·ByungGu Cheon
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Abstract

Detector calibration is very important for the long-term operation. For the purposes of simple and precise calibration, we developed a new portable calibration source using UVLED to calibrate the fluorescence detector of the Telescope Array experiment (TA). The UVLED is light (less than 1 kg) and its setup is quick and easy. Therefore, a single source will be used instead of the calibration sources that TA currently uses. The UVLED emits 369 nm wavelength and ~70 pJ of photons which are calibrated with 5% accuracy us-ing photo-diode. It has a particular unit, which is an internal heater, to keep the temperature constant and avoiding temperature dependency on light yield. The first result of calibration for 24 detectors is xx pho-tons/faced count for 369 nm photons with 6% uncertainty. It is in agreement with the result of the current calibration sources of TA.

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Sungrae Im, Bokkyun Shin, Ikeda Daisuke, Stan Thomas, ByungGu Cheon. 2018-12-04. Calibration of photomultiplier using UVLED. https://arxiv.org/abs/1812.01364

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