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Improvements and Extensions of the Neutron Cross Section and Fluence Standards



Allan D. Carlson, V G. Pronyaev, R. Capote, F. J. Hambsch, F. Kappeler, C. Lederer, A Mengoni, R O. Nelson, A.J.M Plompen, P Schillebeeckx, S Simakov, S. Tagesen, H Vonach, A Vorobyev, A Wallner


Updated evaluations of the standards are needed within a few years for new versions of several cross section libraries, e.g.; ENDF/B and JEFF, that have been planned. To update the standards, a collaboration, supported by an IAEA Data Development Project, was established. Objectives of this project are to continuously and critically review new experiments for inclusion in the standards database, make improvements where necessary to the existing database, study improved evaluation procedures and codes for performing the evaluations, maintain those codes, consider extensions in energy of some of the standards, and investigate inclusion of reference data that are not as well known as the standards but can be very useful in the measurement of certain types of cross sections. Also included is an effort to improve evaluations of 235U thermal and 252Cf spontaneous fission neutron spectra. Before this project was initiated, there were very longperiods between standards evaluations [1] that can now be signi cantly shortened. The anticipation is that a new Corresponding author: carlson [at] (carlson[at]nist[dot]gov) standards evaluation can be available whenever one is needed by a major evaluation library. In addition to this project, the recently established Collaborative International Evaluated Library Organization,[2], will be supporting e orts to improve the standards.
Nuclear Data Sheets


fission, neutron spectra, standards


Carlson, A. , Pronyaev, V. , Capote, R. , Hambsch, F. , Kappeler, F. , Lederer, C. , Mengoni, A. , Nelson, R. , Plompen, A. , Schillebeeckx, P. , Simakov, S. , Tagesen, S. , Vonach, H. , Vorobyev, A. and Wallner, A. (2014), Improvements and Extensions of the Neutron Cross Section and Fluence Standards, Nuclear Data Sheets, [online], (Accessed February 27, 2024)
Created April 4, 2014, Updated November 10, 2018