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arXiv · 1506.05150

Development of a Compton imager based on bars of scintillator

A. M. L. MacLeod·P. J. Boyle·D. S. Hanna·P. R. B. Saull·L. E. Sinclair·H. C. J. Seywerd
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Abstract

We have developed a compact Compton gamma-ray imager with a large field of view and a low channel-count that is capable of quickly localizing gamma-ray sources in the few hundred keV - several MeV range. The two detector planes (scatter and absorber) employ bars of NaI(Tl) read out by photomultiplier tubes (PMTs) located at each end. The long-range imaging performance has been tested from 392 keV to 1274 keV. An angular resolution measure of 2.72 +/- 0.06 degrees and an efficiency of (1.79 +/- 0.04) x 10^(-3) at 662 keV is obtained. A Cs-137 (662 keV) source equivalent to a 10 mCi source 40 m away can be located in 60 seconds with an uncertainty of about a degree. No significant degradation in imaging performance is observed for source angles up to 40 degrees off axis.

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A. M. L. MacLeod, P. J. Boyle, D. S. Hanna, P. R. B. Saull, L. E. Sinclair, H. C. J. Seywerd. 2015-06-16. Development of a Compton imager based on bars of scintillator. https://doi.org/10.1016/j.nima.2014.08.012.

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