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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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-EM awards $74.8M Oak Ridge support services contract
The Department of Energy’s Office of Environmental Management has awarded a five-year contract worth up to $74.8 million to Independent Strategic Management Solutions for professional support services at the Oak Ridge Office of Environmental Management site in Oak Ridge, Tenn.
N. Tsoulfanidis, B. W. Wehring, M. E. Wyman
Nuclear Science and Engineering | Volume 43 | Number 1 | January 1971 | Pages 42-53
Technical Paper | doi.org/10.13182/NSE71-A21244
Articles are hosted by Taylor and Francis Online.
Previously, absolute measurements were reported for the time-dependent beta energy spectra from fission fragments for electron energies >0.75 MeV. The fragments were produced in the thermal-neutron fission of 235U. To obtain results for electron energies below 0.75 MeV and to provide overlap with the previous results, absolute measurements were made of the time-dependent energy spectra using an experimental system specifically designed for the electron energy range of 0.1 to 1.0 MeV. In this system, a vacuum chamber housed a thin plastic scintillator for the detection of the low-energy electrons, a source foil which was fissioned in a thermal-neutron beam, and a surface-barrier detector for the monitoring of the fission rate. The source foil consisted of 10.4 mg/cm2 of 235U covered and sealed to form a localized source of fission fragments. A deposit of 138 µg/cm2 of 235U on the outside of this foil facing the surface-barrier detector provided the fission fragments for the monitor. Electron energy spectra were measured for the cases of (i) spectrum build-up after initiation of a constant fission rate in a clean foil, (ii) spectrum decay after termination of 8 h of a constant fission rate, and (iii) spectrum decay following a sudden burst of fission produced by a reactor power pulse. The resulting spectra were corrected for the effects of energy resolution and source thickness by unfolding them with the use of a measured system response function. The time-dependent energy measurements for the low-energy betas were combined with the previous measurements for the high-energy betas and the results are presented in tables and graphs. Also given are the total number of betas per fission and the total beta energy per fission for various times during the build-up or the decay of the spectra. Comparisons are made with previous experimental and theoretical work.
