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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting 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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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
S. K. Trikha, P. S. Grover
Nuclear Science and Engineering | Volume 26 | Number 4 | December 1966 | Pages 447-452
Technical Paper | doi.org/10.13182/NSE66-A18415
Articles are hosted by Taylor and Francis Online.
In the case of crystalline (coherent) moderators, it has been observed that the trapping of neutrons in the Bragg peaks greatly affects the decay of a neutron pulse from inside small assemblies and leads to a much larger value of the observed decay constant as compared to the theoretical limit. In the present paper we report a theoretical study of the pulsed neutron problem in finite assemblies of incoherent solid moderators. We find that even in the absence of the trapped neutrons, it will take a very long time for the decay constant to approach the theoretical asymptotic limit (υ∑s)min. A study of transient spectra has also been made in these assemblies. We find that for large assemblies (B2 < ), the value of λ calculated from the study of transient spectra agrees well with the asymptotic decay constant. However, for small assemblies, the equilibrium is not attained within 600 μsec, the time limit of our studies.