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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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G. C. Pomraning
Nuclear Science and Engineering | Volume 52 | Number 1 | September 1973 | Pages 144-145
Technical Note | doi.org/10.13182/NSE73-A23298
Articles are hosted by Taylor and Francis Online.
Consider one-speed neutron transport in an infinite medium. Let a neutron be released from the origin at time zero. In a recent paper, a probabilistic argument was used to derive an exact expression, for an arbitrary scattering law, giving the neutron’s mean square distance from the origin as a function of time. This result can be derived in a much simpler manner by merely forming the appropriate spatial and angular moments of the transport equation.