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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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.
H. C. Corben
Nuclear Science and Engineering | Volume 5 | Number 2 | February 1959 | Pages 127-131
Technical Paper | doi.org/10.13182/NSE59-A25565
Articles are hosted by Taylor and Francis Online.
The space-independent pile kinetic equations are solved to give the excess reactivity explicitly in terms of the rate of change of power and an integral over the past history of the power, the precursor densities being eliminated algebraically from the equations. The need for digital computations for determining the reactivity from a given power trace is thereby reduced. The solution is applicable to arbitrary variations of power with time and is examined in detail for the case of small damped oscillations, where it leads to simple algebraic expressions for the gain and phase angle. The behavior of the reactivity as a function of time is also computed for the case of a power fluctuation occurring during a short time interval, for a power trace which increases exponentially and then stays constant, and for a rapidly decaying power burst.
