Proof of principle of a high-spatial-resolution, resonant-response γ-ray detector for Gamma Resonance Absorptionin 14N

Journal of Instrumentation (Impact Factor: 1.4). 03/2011; 6(02). DOI: 10.1088/1748-0221/6/02/P02008
Source: arXiv


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.

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    • "In 2005 the Soreq, PTB and Bern University collaboration investigated a capillary array of 20 µm in diameter fibres, developed by the CHORUS collaboration at CERN. The capillaries were filled with high-refractive-index liquid scintillator developed at Soreq for a Gamma-ray Resonance Absorption (GRA) detector [8]. The detector was tested with gamma-rays and mixed gamma and neutron events, produced by radioactive sources. "
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