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Allan D. Carlson (Assoc)

Dr. Carlson joined NBS in 1972 as Manager of the Van de Graaff facility. His work was focused on measurements of neutron standard cross sections using monoenergetic neutrons. In addition to Dr. Carlson’s activities at the Van de Graaff, he became involved in the neutron cross section standards work at the NBS linac and was promoted to the position of Coordinator of the Van de Graaff and linac neutron cross section standards programs. In this role he coordinated and managed the standards activities of the Van de Graaff and linac experimental groups. He also maintained an active role in the measurements of important standard cross sections.

The need for standard cross section data that could not be obtained with the NBS facilities led to significant collaborations with staff members at Los Alamos National Laboratory, Oak Ridge National Laboratory and Ohio University.

Recently his efforts have been focused on evaluations of the neutron cross section standards. These standards are essential for determinations of the nuclear cross sections for the United States nuclear data files (ENDF/B). He is the responsible person for the standards for the Cross Section Evaluators Working Group. He has worked on the evaluation of the neutron cross section standards for ENDF/B-IV through ENDF/B-VIII. He led an effort to form an IAEA nuclear data development project that would provide some resources for continually improving the standards. He has chaired all the meetings of this project. These standards will also be used by the world wide nuclear data community including Europe, China, Japan, Russia, Britain and Korea.

Selected Publications

A.D. Carlson et al., Evaluation of the Neutron Data Standards, Nucl. Data Sheets 148, 143, (2018).

A.D. Carlson in Applying a Template of Uncertainties to Updating Uncertainties of 239Pu(n,f) Cross-section Data in the Neutron Data Standards Database, Nucl. Data Sheets 163 228 (2020) 

N. V. Kornilov, S. M. Grimes, T. N. Massey, C. E. Brient, D. E. Carter,  J. E. O’Donnell, K. W. Cooper, A. D. Carlson, F. B. Bateman, C. R. Heimbach, N. Boukharouba, A high precision tagged neutron n-p scattering measurement at 14.9 MeV, Nucl. Sci. Eng. 194 335 (2020)

A.D. Carlson, O.A. Wasson, P.W. Lisowski, J.L. Ullmann, and N.W. Hill, Measurements of the 235U(n,f) Cross Section in the 3 to 30 MeV Neutron Energy Region, Proc. of the International Conference on Nuclear Data for Science and Technology, 13 17 May, 1991, Jülich, Fed. Rep. of Germany, S. M. Qaim, Ed., pp 518 520.

O.A. Wasson, A.D. Carlson, and K.C. Duvall, Measurement of the 235U Neutron Induced Fission Cross Section at 14.1 MeV, Nucl. Sci. Eng., 80, 282 303 (1982).


Recent Work Leading Toward a New Evaluation of Neutron Standards

Allan D. Carlson, V G. Pronyaev, R. Capote, G M. Hale, F. J. Hambsch, T Kawano, S. Kunieda, W Mannhart, R O. Nelson, D. Neudecker, P Schillebeeckx, S Simakov, P Talou, X Tao, D. L. Smith, W Wang, A. Wallner
A number of national cross section libraries are planning new versions of their libraries including ENDF/B and JEFF. The first step in producing these new

Toward a New Evaluation of the Neutron Standards

Allan D. Carlson, V G. Pronyaev, R. Capote, G M. Hale, F. J. Hambsch, T Kawano, S. Kunieda, R O. Nelson, D. Neudecker, P Schillebeeckx, S Simakov, D L. Smith, X Talou, A Wallner, W Wang
A new version of the ENDF/B library has been planned. The first step in producing this new library is evaluating the neutron standards. An evaluation is now

New Methods for Measurement of Neutron Detector Efficiency up to 20 MeV

Fred B. Bateman, Allan D. Carlson, N. A. Kornilov, S M. Grimes, T N. Massey, C E. Brient, D E. Carter, J E. O'Donnell, R. C. Haight, N Boukharouba
A new approach to neutron detector effciency has been taken. A neutron detector has been calibrated with a Cf-252 source at low energy. The calibration was

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
Created October 9, 2019, Updated December 8, 2022