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arXiv · 1801.02623

High rate tests of the photon detection system for the LHCb RICH Upgrade

Michele Piero Blago·Floris Keizer
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Abstract

The photon detection system for the LHCb RICH Upgrade consists of an array of multianode photomultiplier tubes (MaPMTs) read out by custom-built modular electronics. The behaviour of the whole chain was studied at CERN using a pulsed laser. Threshold scans were performed in order to study the MaPMT pulse-height spectra at high event rates and different photon intensities. The results show a reduction in photon detection efficiency at 900 V bias voltage, marked by a 20 % decrease in the single-photon peak height, when increasing the event rate from 100 kHz to 20 MHz. This reduction was not observed at 1000 V bias voltage.

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Michele Piero Blago, Floris Keizer. 2018-01-08. High rate tests of the photon detection system for the LHCb RICH Upgrade. https://doi.org/10.1016/j.nima.2017.02.014

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