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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Latest News
College students help develop waste-measuring device at Hanford
A partnership between Washington River Protection Solutions (WRPS) and Washington State University has resulted in the development of a device to measure radioactive and chemical tank waste at the Hanford Site. WRPS is the contractor at Hanford for the Department of Energy’s Office of Environmental Management.
Scott D. Ramsey, Gregory J. Hutchens
Nuclear Science and Engineering | Volume 173 | Number 2 | February 2013 | Pages 197-205
Technical Note | doi.org/10.13182/NSE11-34
Articles are hosted by Taylor and Francis Online.
A quantity that is frequently of interest in stochastic neutronics calculations is the probability of extinction (POE), or its complement, the survival probability. Even within the simplest stochastic point kinetics formulations, the POE is typically extracted from numerical calculations or approximated. An example of the latter strategy involves the truncation of the fission multiplicity distribution at two, resulting in the “quadratic approximation.” While this methodology yields closed-form results for the POE, it is valid only for supercritical multiplication near unity. In this technical note, we attempt to obviate fission multiplicity truncation in the construction of transient and infinite time limit closed-form POE solutions. In the infinite time limit, we arrive at the necessity of solving a quintic algebraic equation; we provide a brief discussion of the mature formalism available for solving quintic equations and generate a variety of simple representations using hypergeometric series. We evaluate and discuss both the new and existing approximations in the context of an example 235U system and compare their validity over a range of supercritical multiplication factors.