Search for luminescent materials under 14MeV neutron irradiation

Abstract A radiation detection system utilizing radiation-resistant optical fibers and luminescent materials will have several advantages, such as compactness and robustness, and can be a strong candidate for diagnostics of fusion neutrons. Luminescent materials – important components of an optical system – that exhibit luminescence under fast neutron irradiation were studied. Commercially available luminescent materials, such as ZnS:Ag, ZnS:Cu, SrAl 2 O 4 :Eu 2+ , Dy 3+ , and Sr 4 Al 14 O 25 :Eu 2+ , Dy 3+ exhibit luminescence under 14 MeV neutron irradiation. The materials excluding ZnS:Ag showed radiation resistance for a fast neutron fluence of up to 10 14 n/cm 2 . The luminescence characteristics of Sr 4 Al 14 O 25 :Eu 2+ , Dy 3+ that have three apparent peaks were also examined under proton irradiation. The compounds exhibited the same luminescence peaks under fast neutron irradiation, which can be attributed to their dopants, namely, Dy 3+ and Eu 2+ , and the intensity ratio of Eu 2+ to Dy 3+ showed dependence on incident energy and radiation.