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International Key Comparison of Neutron Fluence Measurements in Monoenergetic Neutron Fields – CCRI(III)-K11



Maynard S. Dewey, V. Gressier, A. C. Bonaldi, David M. Gilliam, H. Harano, A. Masuda, T Matsumoto, N. Moiseev, Jeffrey S. Nico, R. Notle, S. Oberstedt, N. J. Roberts, S. Rottger, D. J. Thomas


To ensure the validity of their national standards, National Metrology Institutes, NMIs, participate regularly in international comparisons. In the area of neutron metrology, Section III of the Consultative Committee for Ionizing Radiation is in charge of the organization of these comparisons. From September 2011 to October 2012, the eleventh key comparison, named CCRI(III)-K11, took place at the AMANDE facility of the LNE-IRSN, in France. Participants from nine NMIs came with their own primary reference instruments, or instruments traceable to primary standards, with the aim of determining the neutron fluence, at 1 m distance from the target in vacuum, per monitor count at four monoenergetic neutron fields: 27 keV, 565 keV, 2.5 MeV and 17 MeV. The key comparison reference values (KCRV) were evaluated as the weighted mean values of the results provided by seven participants. The uncertainties of each KCRV are between 0.9 % and 1.7 %. The degree of equivalence (DoE), defined as the deviation of the result reported by the laboratories for each energy from the corresponding KCRV, and the associated expanded uncertainty are also reported and discussed


CCRI(III), mono-energetic neutron fields, neutron fluence, neutron metrology


Dewey, M. , Gressier, V. , Bonaldi, A. , Gilliam, D. , Harano, H. , Masuda, A. , Matsumoto, T. , Moiseev, N. , Nico, J. , Notle, R. , Oberstedt, S. , Roberts, N. , Rottger, S. and Thomas, D. (2014), International Key Comparison of Neutron Fluence Measurements in Monoenergetic Neutron Fields – CCRI(III)-K11, Metrologia, [online], (Accessed April 12, 2024)
Created November 3, 2014, Updated February 19, 2017