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Updated: Feb 10, 2026
Molten-Salt Synthesis of Complex Metal Oxide Nanoparticles
Published on: October 27, 2018
Thin NaI(Tl) crystals to enhance the detection sensitivity for molten 241Am sources
Pauli Peura1, Camille Bélanger-Champagne1, Paula Eerola2
1Helsinki Institute of Physics, University of Helsinki, P.O.B. 64, FI-00014, Finland.
Abstract:
A thin 5-mm NaI(Tl) scintillator detector was tested with the goal of enhancing the detection efficiency of 241Am gamma and X rays for steelworks operations. The performance of a thin (5 mm) NaI(Tl) detector was compared with a standard 76.2-mm thick NaI(Tl) detector. The 5-mm thick detector crystal results in a 55% smaller background rate at 60 keV compared with the thicker detector, translating into the ability to detect 30% weaker 241Am sources. For a 5 mm thick and 76.2 mm diameter NaI detector in the ladle car tunnel at Outokumpu Tornio Works, the minimum activity of a molten 241Am source that can be detected in 5 s with 95% probability is 9 MBq.
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