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Mathematics & Computation
Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Penn State and Westinghouse make eVinci microreactor plan official
Penn State and Westinghouse Electric Company are working together to site a new research reactor on Penn State’s University Park, Pa., campus: Westinghouse’s eVinci, a HALEU TRISO-fueled sodium heat-pipe reactor. Penn State has announced that it submitted a letter of intent to host and operate an eVinci reactor to the Nuclear Regulatory Commission on February 28 and plans to engage with the NRC on specific siting decisions. Penn State already boasts the Breazeale reactor, which began operating in 1955 as the first licensed research reactor at a university in the United States. At 70, the Breazeale reactor is still in operation.
C. B. Bigham
Nuclear Science and Engineering | Volume 6 | Number 5 | November 1959 | Pages 379-385
Technical Paper | doi.org/10.13182/NSE59-A25675
Articles are hosted by Taylor and Francis Online.
The dependence on neutron temperature of the ratio of thermal neutron fission cross sections, , has been measured in heavy water moderator. Satisfactory agreement was obtained with the temperature dependence of the cross sections for Maxwellian neutron spectra calculated by C. H. Westcott from the neutron cross section energy dependence. Measurements have also been made of the spatial distribution of neutron temperature in a tank of heavy water. At the side of the tank facing the graphite thermal column neutron source, an apparent temperature difference between neutron temperature and D2O temperature (initially 44°C) decreased with a relaxation length of about one inch for points inside the tank.