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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
R. G. Alsmiller, Jr., D. C. Irving, H. S. Moran
Nuclear Science and Engineering | Volume 32 | Number 1 | April 1968 | Pages 56-61
Technical Paper | doi.org/10.13182/NSE68-A18824
Articles are hosted by Taylor and Francis Online.
The straightahead approximation, i.e., the approximation that the secondary particles from nucleon-nucleus collisions are emitted in the direction of the incident nucleon, is often used in space-vehicle shielding studies. The validity of this approximation has been tested by comparing calculations made with the angular distribution of secondary particles properly taken into account with calculations using the approximation. Comparisons between the calculations are given for both monoenergetic protons and a typical flare spectrum normally incident on slab shields followed by tissue. The results indicate that the approximation is sufficiently accurate to justify its use in obtaining estimates of the secondary-particle contribution to the dose behind thin shields.