Proof of principle of a high-spatial-resolution, resonant-response gamma-ray detector for Gamma Resonance Absorption in 14N

TL;DR

This paper presents a proof-of-principle for a high-resolution gamma-ray detector based on a micrometric glass capillary array, capable of distinguishing particle types for improved nitrogen detection in GRA.

Contribution

It introduces a novel high-spatial-resolution detector for Gamma Resonance Absorption in 14N, combining simulation and experimental validation.

Findings

Proton tracks are distinguishable from electron tracks based on length and light intensity.

The detector demonstrates potential for high-resolution nitrogen detection.

Simulations align with experimental results, confirming detector capability.

Abstract

The development of a mm-spatial-resolution, resonant-response detector based on a micrometric glass capillary array filled with liquid scintillator is described. This detector was developed for Gamma Resonance Absorption (GRA) in 14N. GRA is an automatic-decision radiographic screening technique that combines high radiation penetration (the probe is a 9.17 MeV gamma ray) with very good sensitivity and specificity to nitrogenous explosives. Detailed simulation of the detector response to electrons and protons generated by the 9.17 MeV gamma-rays was followed by a proof-of-principle experiment, using a mixed gamma-ray and neutron source. Towards this, a prototype capillary detector was assembled, including the associated filling and readout systems. Simulations and experimental results indeed show that proton tracks are distinguishable from electron tracks at relevant energies, on the basis of a criterion that combines track length and light intensity per unit length.