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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fusion Science and Technology
August 2025
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The newest era of workforce development at ANS
As most attendees of this year’s ANS Annual Conference left breakfast in the Grand Ballroom of the Chicago Downtown Marriott to sit in on presentations covering everything from career pathways in fusion to recently digitized archival nuclear films, 40 of them made their way to the hotel’s fifth floor to take part in the second offering of Nuclear 101, a newly designed certification course that seeks to give professionals who are in or adjacent to the industry an in-depth understanding of the essentials of nuclear energy and engineering from some of the field’s leading experts.
Hiroshi Nakashima, Shun-Ichi Tanaka, Tomoo Suzuki
Fusion Science and Technology | Volume 16 | Number 3 | November 1989 | Pages 365-376
Technical Paper | Shielding | doi.org/10.13182/FST89-A29127
Articles are hosted by Taylor and Francis Online.
An experiment was carried out to study the behavior of 14-MeV neutrons incident to a large cavity composed of mortar coated with stainless steel, which simulates a neutral beam injector (NBI) in a tokamak fusion reactor. Fast neutron spectra and reaction rate distributions were measured inside the cavity with a 5.06-cm-high × 5.06-cm-diam NE-213 spectrometer as well as 232Th and 235U fission counters. The experimental results were analyzed with a Monte Carlo MCNP-3 code, using nuclear data files from the JENDL series and from ENDF/B-IV. Calculations with two discrete ordinates codes, DOT3.5 and BERMUDA-2DN, using ENDF/B-IV and JENDL nuclear data files, were also compared with the measurements to study their applicability for NBI design. For fast neutrons, the MCNP calculations are in good agreement with the measurements. Moreover, comparison between the DOT3.5 and BERMUDA-2DN calculations showed the significant effect of the Legendre expansion of neutron scattering in the high-energy region. For low-energy neutrons, the DOT3.5 code calculations agreed with the measurements, while the MCNP code could not successfully reproduce the measurements. The experiments also suggested that the ratios of thermal and epithermal neutrons were constant for the 14-MeV neutrons coming into the cavity.
