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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.
Noriaki Nakao, Hiroshi Nakashima, Takashi Nakamura, Shun-ichi Tanaka, Susumu Tanaka, Kazuo Shin, Mamoru Baba, Yukio Sakamoto, Yoshihiro Nakane
Nuclear Science and Engineering | Volume 124 | Number 2 | October 1996 | Pages 228-242
Technical Paper | doi.org/10.13182/NSE96-A28574
Articles are hosted by Taylor and Francis Online.
The energy spectra of neutrons that penetrate 25- to 200-cm-thick concrete shields are measured using 40- and 65-MeV quasi-monoenergetic neutron sources at the 90-MeV AVF cyclotron of the Takasaki Ion Accelerator Facility for Advanced Radiation Application at the Japan Atomic Energy Research Institute. Source neutrons are produced at 3.6- and 5.2-mm-thick 7Li targets bombarded 43- and 68-Me Vprotons, respectively, and their spectra are measured with a proton recoil counter telescope and the time-of-flight method. In the shielding experiment, a BC501A organic liquid scintillator and a multimoderator spectrometer with a 3He counter (the Bonner Ball) are used as the neutron spectrometer. The collimated source neutrons are used to obtain the neutron spectra with the unfolding technique on the neutron beam axis and at off-center positions. MORSE Monte Carlo calculations are performed with the DLC119/HIL086 multigroup cross-section library for comparison with the measured data on the beam axis. The comparison reveals that the calculated spectra are in good agreement with the measured spectra. The measured data at off-center positions are used to check the calculational accuracy of the angular distribution of neutron scattering in the MORSE-CG, DOT3.5 discrete ordinates, and HETC-KFA2 Monte Carlo codes. The MORSE-CG code gives better results than the other two codes.