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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
B. Laponche, M. Brunet, Y. Bouedo
Nuclear Science and Engineering | Volume 48 | Number 3 | July 1972 | Pages 305-318
Technical Paper | doi.org/10.13182/NSE72-A22488
Articles are hosted by Taylor and Francis Online.
A method is described for the analysis of oscillation measurements in critical assemblies where fissions are produced predominantly by thermal neutrons. The oscillation method developed in the CEA deals with the measurement of two signals: the “global” signal, which gives a representation of the sample reactivity, and the “local” signal, which gives the variation of the neutron density at the vicinity of the sample. Using a double calibration of the reactor by samples of enriched or depleted uranium and boronated uranium, it is possible to obtain independently the absorption and production reaction rates for plutonium in each sample, as a function of 235U reaction rates. The equivalent sample method is a more recent development and is based on the fact that a given perturbation of the absorption cross section, with any law of variation with energy in the thermal region, can be replaced by an absorption of well-known variation with energy which has the same effect on the neutronic density in the reactor beyond a small distance where spectrum effects are still appreciable. A series of measurements of uranium/plutonium rods performed in the CESAR reactor, from 20 to 400°C, is analyzed, and modifications of the absorption and fission cross sections of plutonium isotopes are proposed.