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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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. E. Howe, J. C. Browne, R. J. Dougan, R. J. Dupzyk, J. H. Landrum
Nuclear Science and Engineering | Volume 77 | Number 4 | April 1981 | Pages 454-462
Technical Paper | doi.org/10.13182/NSE81-A18958
Articles are hosted by Taylor and Francis Online.
The fission neutron multiplicity, , of 242mAm(n,f) was measured relative to that of 235U(n,f) using the neutron time-of-flight facility at the Lawrence Livermore National Laboratory 100-MeV electron Linac. Incident neutron energies ranged from 0.037 to 30 MeV. Fission fragments were detected using two hemispherical ionization chambers each containing ∼400 µg of 99.2% pure 242mAm. A separate fission chamber with 8.3 mg of 235U was situated between the two 242Am chambers and provided a normalization at every data point. Fission neutrons were detected in a liquid benzene scintillator using pulse-shape discrimination to separate gamma rays from neutrons. A comparison of the measured energy dependence of is made with semi-empirical models of neutron emission from the actinides.