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November 9–12, 2025
Washington, DC|Washington Hilton
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ANS sends waste policy recommendations to DOE
The American Nuclear Society has sent a letter to Energy Secretary Chris Wright with a set of recommendations for the Department of Energy to take to establish an effective national program to manage the storage, reprocessing, and final disposal of U.S. commercial used nuclear fuel.
T. Matsumura
Nuclear Science and Engineering | Volume 183 | Number 3 | July 2016 | Pages 407-420
Technical Paper | doi.org/10.13182/NSE15-86
Articles are hosted by Taylor and Francis Online.
The neutron escape probability from a rectangular cell is investigated for the collision probability method. Since the numerical calculation of the escape probability requires multiple integrations, resulting in a long computing time, semianalytical approximation of the multiple integrations is proposed to reduce the computing time. By approximating the result of integration in the z-direction by a polynomial expression divided into ranges, it is possible to perform the integrations in the x- and y-directions analytically. The computing time of the present semianalytical approximation is reduced by one to two orders of magnitude compared with that required for the conventional numerical integration. Moreover, a lookup escape probability table for rectangular cells calculated using the semianalytical approximation enables the calculation of the escape probability for an arbitrary rectangle with a much shorter computing time and practical precision (<0.1% error). In addition, a method of applying the semianalytical approximation and a lookup table to the collision probability calculation for an x-y geometry is discussed.