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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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World Bank, IAEA partner to fund nuclear energy
The World Bank and the International Atomic Energy Agency signed an agreement last week to cooperate on the construction and financing of advanced nuclear projects in developing countries, marking the first partnership since the bank ended its ban on funding for nuclear energy projects.
Matthew A. Gonzales, Brian C. Kiedrowski, Anil K. Prinja, Forrest B. Brown
Nuclear Science and Engineering | Volume 191 | Number 1 | July 2018 | Pages 1-45
Technical Paper | doi.org/10.1080/00295639.2018.1442546
Articles are hosted by Taylor and Francis Online.
The heavy-gas model with specific energy-dependent absorption cross sections is used to construct analytical, semi-analytical, and numerical free-gas scattering benchmarks for the neutron spectrum, effective multiplication factor k, and temperature coefficient in an infinite, homogeneous medium. The energy dependences considered are piecewise constant, constant plus inverse in energy, and piecewise linear. Analytic forms for k and in terms of hypergeometric functions are obtained for piecewise-constant absorption with two energy ranges and for constant-plus-inverse-in-energy absorption. Analogous semi-analytical integral expressions are obtained for piecewise-linear absorption with two energy ranges. Numerical solutions of a linear system are obtained for piecewise-constant and piecewise-linear absorption for greater than two energy ranges. The heavy-gas model solutions of k are compared with continuous-energy Monte Carlo calculations; the results converge to the heavy-gas model with increasing target mass ratio A, demonstrating the heavy-gas model’s utility as a verification benchmark.