Multigap RPC time resolution to 511 keV annihilation photons

TL;DR

This study evaluates the time resolution of multigap resistive plate counters (MRPCs) for 511 keV gamma rays using experimental measurements and simulations, achieving sub-nanosecond precision relevant for medical imaging.

Contribution

It provides the first detailed measurement of MRPC time resolution for 511 keV photons and supports findings with GEANT4 simulations, advancing detector performance understanding.

Findings

Time resolution of 376 ps for single MRPC with four gaps.

Time resolution of 312 ps when using two detector pairs.

Experimental results are supported by GEANT4 simulation analysis.

Abstract

The time resolution of Multigap Resistive Plate Counters (MRPCs) to $511$ keV gamma rays has been investigated using a $^{22}$Na source and four detectors. The MRPCs time resolution has been derived from the Time-of-Flight information, measured from pairs of space correlated triggered events. A GEANT4 simulation has been performed to analyze possible setup contributions and to support experimental results. A time resolution (FWHM) of $376$ ps and $312$ ps has been measured for a single MRPC with four $250$ $\mu$m gas gaps by considering respectively one and two independent pairs of detectors.