Silicon photomultiplier-based Compton Telescope for Safety and Security (SCoTSS)

TL;DR

The paper presents SCoTSS, a portable silicon photomultiplier-based Compton gamma imager designed for security and safety, capable of high-resolution imaging within a minute over a broad energy range.

Contribution

It introduces a novel, compact SiPM-based Compton imager optimized for field use, with detailed performance evaluation demonstrating its effectiveness.

Findings

Achieves 1-degree image resolution at 40 meters for a 10 mCi source.

Operates effectively across gamma energies from 344 keV to 1274 keV.

Provides rapid imaging within approximately one minute.

Abstract

A Compton gamma imager has been developed for use in consequence management operations and in security investigations. The imager uses solid inorganic scintillator, known for robust performance in field survey conditions. The design was constrained in overall size by the requirement that it be person transportable and operable from a variety of platforms. In order to introduce minimal dead material in the path of the incoming and scattered gamma rays, custom silicon photomultipliers (SiPMs), with a thin glass substrate, were used to collect the scintillation light from the scatter layers. To move them out of the path of the gamma rays, preamplification electronics for the silicon photomultipliers were located a distance from the imager. This imager, the Silicon photomultiplier Compton Telescope for Safety and Security (SCoTSS) is able to provide a one-degree image resolution in a plus-minus 45 degree field of view for a 10 mCi point source 40 m distant, within about one minute, for gamma-ray energies ranging from 344 keV to 1274 keV. Here, we present a comprehensive performance study of the SCoTSS imager.