The analysis of complex mixed-radiation fields using near real-time imaging.
A new mixed-field imaging system has been constructed at Lancaster University using the principles of collimation and back projection to passively locate and assess sources of neutron and gamma-ray radiation. The system was set up at the University of Manchester where three radiation sources: (252)Cf, a lead-shielded (241)Am/Be and a (22)Na source were imaged. Real-time discrimination was used to find the respective components of the neutron and gamma-ray fields detected by a single EJ-301 liquid scintillator, allowing separate images of neutron and gamma-ray emitters to be formed. (252)Cf and (22)Na were successfully observed and located in the gamma-ray image; however, the (241)Am/Be was not seen owing to surrounding lead shielding. The (252)Cf and (241)Am/Be neutron sources were seen clearly in the neutron image, demonstrating the advantage of this mixed-field technique over a gamma-ray-only image where the (241)Am/Be source would have gone undetected.
Department of Engineering, Lancaster University, Lancaster LA1 4YR, UK j.beaumont@lancaster.ac.uk.
Jonathan
J
Beaumont
Createc Ltd., Derwent Mills Commercial Park, Cockermouth, Cumbria CA13 0HT, UK.
Matthew P
MP
Mellor
Department of Engineering, Lancaster University, Lancaster LA1 4YR, UK.
Malcolm J
MJ
Joyce
D000576:Americium; D001608:Beryllium; D002142:Californium / Q000737:chemistry*; D004867:Equipment Design; D005720:Gamma Rays; D009502:Neutrons; D011829:Radiation Dosage; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods; D012588:Scintillation Counting; D012964:Sodium / Q000737:chemistry; D006113:United Kingdom
D002142:Californium; D012964:Sodium; D001608:Beryllium; D000576:Americium