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Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
Robert J. Tuttle
Nuclear Science and Engineering | Volume 21 | Number 4 | April 1965 | Pages 451-462
Technical Paper | doi.org/10.13182/NSE65-A18789
Articles are hosted by Taylor and Francis Online.
The variation of neutron importance with energy and position has been investigated in a multiregion critical assembly having a series of test regions typical of slightly epithermal to fast power reactors. Values of neutron importance at the center of the test regions were measured using neutron sources and a reactivity oscillator. The variation of neutron importance with position was determined using neutron sources in conjunction with a dynamic reactivity-measurement technique. Analysis of data from similar beryllium- and carbon-moderated test regions indicates the significance of the Be(n, 2n) reaction. The neutron sources used in this study were Po-Be, Po-B11, Po-CaF2, Po-Li7, Mock Fission and Sb-Be. Published source spectra were used in the analysis of the data; the Mock-Fission-source spectrum was determined by gamma-ray spectroscopy. Relative yields of these sources were determined by calibration in a manganese sulfate bath.
