Design and experimental test of a novel double stack MRPC detector for medical imaging applications

Abstract

The Resistive Plate Chambers (RPC) are parallel-plate gaseous detectors, thanks to their good spatial resolution and high time resolution in comparison to the scintillation detectors, have been recently used for time of flight measurements in PET imaging systems. In this work, design and testing of a new Multi-gap RPC (MRPC) with a suitable time and energy resolution for medical imaging applications is proposed. This MRPC detector, consists of glass plates with optimum thickness to achieve acceptable detection efficiency. In addition, the optimum thickness of gas gaps is estimated to improve the time response by reducing the space-charge effect. The electrodes which are used to apply the electric field are special graphite foils (0.07 mm thick, 0.7 g/cm3 density and 3kΩ/cm2 surface resistivity) with the purity of 99.95%. The arrangement of the vertical and horizontal readout strips are also optimized to achieve more uniformity of electric field in each pixel. The Monte Carlo simulation and experimental results show that this low-cost detector has a suitable ability to be used in PET imaging applications.