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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
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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Fusion Science and Technology
Latest News
The JT-60SA project
JT-60SA (Japan Torus-60 Super Advanced) is the world’s largest superconducting tokamak device. Its goal is the earlier realization of fusion energy (see Fig. 1). Fusion is the energy that powers the Sun, and just 1 gram of deuterium-tritium (D-T) fuel produces enormous energy—the equivalent of 8 tons of crude oil.
Last fall, the JT-60SA project announced an important milestone: the achievement of the tokamak’s first plasma. This article describes the objectives of the JT-60SA project, achievements in the operation campaign for the first plasma, and next steps.
Takashi Nakamura, Toshiso Kosako
Nuclear Science and Engineering | Volume 77 | Number 2 | February 1981 | Pages 168-181
Technical Paper | doi.org/10.13182/NSE81-A21351
Articles are hosted by Taylor and Francis Online.
The skyshine of monoenergetic neutrons directed upward from sources both as a vertically collimated beam and as a point isotropic cone fixed on the ground has been calculated systematically by a Monte Carlo method for distances up to ∼2 km from the source. The energy of the neutrons ranged from 14 MeV to thermal. The calculated skyshine spectra approach an approximate equilibrium having an approximate 1/E dependence in the keV region beyond about a few hundred metres from the source. The total neutron flux Φ(r) and dose D(r) at a distance r from a source are well represented by a simple formula, and D(r) = QDexp(-r/λD)/r, and the constants , and λD are only dependent on the source-neutron energy. In respect to the dependence of , and QD on the upward aperture, θs, of the cone source and λD change very little with θs, but and QD increase with θs, when θs is larger than 30 deg. This simple formula was applied to evaluate the experimental results of skyshine neutron doses from a fast-neutron source-reactor facility and showed nice agreement.