Title :
Comparison between fast neutron and gamma irradiation of optical fibres
Author :
Henschel, H. ; Köhn, O. ; Lennartz, W. ; Metzger, S. ; Schmidt, H.U. ; Rosenkranz, J. ; Glessner, B. ; Siebert, B.R.L.
Author_Institution :
Fraunhofer-INT, Euskirchen, Germany
Abstract :
A variety of undoped multimode step-index fibres and Ge-doped single mode and graded index fibres is irradiated by 14 MeV neutrons and 60Co gamma rays up to the same total dose. Radiation-induced loss and breaking stress are measured. The loss induced during gamma irradiation of Ge-doped fibres is about 2.5 times higher than during neutron irradiation with the same dose rate, up to a fluence of about 3×1012 cm-2 (14 MeV). This loss ratio decreases to ⩽2.0 after about 1013 cm-2 (14 MeV). Monte Carlo calculations of the dose enhancement as caused by fast recoil protons out of the H-containing acrylate coating are confirmed experimentally. 14 MeV neutron irradiation up to ⩽1013 cm -2 seems to decrease fibre breaking stress by 3-4%, whereas 60Co gamma irradiation up to the same total dose has no effect
Keywords :
Monte Carlo methods; fracture; gamma-ray effects; neutron effects; optical fibre losses; optical fibres; 14 MeV; Ge doped graded index fibre; Ge doped single mode fibre; Monte Carlo simulation; acrylate coating; breaking stress; gamma irradiation; neutron irradiation; optical fibre; proton recoil; radiation induced loss; undoped multimode step index fibre; Coatings; Gamma rays; Loss measurement; Monte Carlo methods; Neutrons; Optical fiber sensors; Optical fiber testing; Optical fibers; Protons; Stress;
Conference_Titel :
Radiation and Its Effects on Components and Systems, 1997. RADECS 97. Fourth European Conference on
Conference_Location :
Cannes
Print_ISBN :
0-7803-4071-X
DOI :
10.1109/RADECS.1997.698960
