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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
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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The Nuclear Family: Empowering parents and caregivers
The Diversity and Inclusion in ANS Committee is hosting a webinar today to celebrate the contributions of parents in the nuclear industry while fostering diversity and inclusion within the community.
Register now: The webinar, from 1:00-2:00 pm ET, will highlight how the nuclear industry supports caregivers, new parents, and new mothers, and will focus on life transitions and parental responsibilities.
Anil K. Prinja, Patrick F. O’Rourke
Nuclear Science and Engineering | Volume 197 | Number 2 | February 2023 | Pages 189-211
Technical Paper | doi.org/10.1080/00295639.2022.2087830
Articles are hosted by Taylor and Francis Online.
The stochastic theory of neutron transport is extended to describe the cumulative distribution of fission numbers and deposited fission energy in a subvolume of a multiplying assembly. Solutions for the probability distributions are obtained using analytical approximations and Monte Carlo simulation in lumped geometry and in symmetric homogeneous and heterogeneous spheres. The results show the development of a power-law tail in the steady-state fission number and deposited energy distributions when the medium is critical, independent of the fission neutron multiplicity distribution and domain heterogeneity. In contrast, the asymptotic decay is faster than exponential in subcritical media due to rapid chain extinction and in supercritical media due to the increasing probability of chain divergence. A formal asymptotic analysis of the problem in lumped geometry with an arbitrary fission neutron multiplicity confirms the existence of power-law tails at critical.