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arXiv · 1909.06107

Fast and Efficient Detection of 511 keV Photons using Cherenkov Light in PbF$_2$ Crystal coupled to a MCP-PMT and SAMPIC Digitization Module

C. Canot·M. Alokhina·P. Abbon·J. P. Bard·D. Breton·E. Delagnes·J. Maalmi·G. Tauzin·D. Yvon·V. Sharyy
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Abstract

We study the possibility to use the Cherenkov light for the efficient detection of 511 keV photons with the goal to use it in TOF-PET. We designed and tested two detection modules consisting of PbF$_2$ crystals attached to Planacon MCP-PMT XP85012. Amplified PMT signals are digitized by the SAMPIC module with high readout rate, up to $10^5$ events/s, and a negligible contribution to the time resolution, below 20 ps (FWHM). We developed a fast 2D scanning system to calibrate the PMT time response and studied in details the timing characteristics of the Planacon PMT. Using a radioactive $^{22}$Na source we measured a detection efficiency of 24% for 511 keV photons in a 10 mm thick crystal and a coincidence resolving time of 280 ps. We analyzed the main factors limiting the time resolution of the large-surface detection module and proposed solutions to improve it, which will be tested in our future project.

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C. Canot, M. Alokhina, P. Abbon, J. P. Bard, D. Breton, E. Delagnes, J. Maalmi, G. Tauzin, D. Yvon, V. Sharyy. 2019-09-13. Fast and Efficient Detection of 511 keV Photons using Cherenkov Light in PbF$_2$ Crystal coupled to a MCP-PMT and SAMPIC Digitization Module. https://doi.org/10.1088/1748-0221/14/12/p12001

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