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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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Nominations open for CNTA awards
Citizens for Nuclear Technology Awareness is accepting nominations for its Fred C. Davison Distinguished Scientist Award and its Nuclear Service Award. Nominations for both awards must be submitted by August 1.
The awards will be presented this fall as part of the CNTA’s annual Edward Teller Lecture event.
George W. Eccleston, Gene L. Woodruff
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 636-651
Technical Paper | doi.org/10.13182/NSE77-A15207
Articles are hosted by Taylor and Francis Online.
Measurements of the near-equilibrium energy spectra of the delayed neutrons associated with fast-neutron-induced fissions of 232Th, 233U, 235U, 238U, and 239Pu are reported over the energy range from 35 to 1500 keV. The fission source spectrum, produced from the 9Be(p, n)9B reaction using 10-MeV protons, approximated a prompt fission spectrum. Over 20% of the delayed neutrons in the measured spectra for each sample appeared below 100 keV. Two large peaks at 41 and 74 keV were observed in the spectra from each nuclide. The measured spectra compare favorably with the data reported by others at energies above 200 keV. However, at energies below this value, our results show a significant increase in the number of delayed neutrons when compared with previously published results.
