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Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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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Fusion Science and Technology
November 2025
Latest News
Modernizing I&C for operations and maintenance, one phase at a time
The two reactors at Dominion Energy’s Surry plant are among the oldest in the U.S. nuclear fleet. Yet when the plant celebrated its 50th anniversary in 2023, staff could raise a toast to the future. Surry was one of the first plants to file a subsequent license renewal (SLR) application, and in May 2021, it became official: the plant was licensed to operate for a full 80 years, extending its reactors’ lifespans into 2052 and 2053.
Naoya Matsui, Takahiro Maegawa, Kazuyuki Noborio, Ryuta Kasada, Yasushi Yamamoto, Satoshi Konishi
Fusion Science and Technology | Volume 64 | Number 3 | September 2013 | Pages 692-696
Test Blanket, Fuel Cycle, and Breeding | Proceedings of the Twentieth Topical Meeting on the Technology of Fusion Energy (TOFE-2012) (Part 2) Nashville, Tennessee, August 27-31, 2012 | doi.org/10.13182/FST13-A19173
Articles are hosted by Taylor and Francis Online.
Neutron transport and energy composition of neutron beam extracted from a cylindrical discharge type fusion device was studied by using the computer simulation code, MCNP. In this study, three concepts of neutron beam optics (reflector and moderator) were proposed and examined; combined reflector which consists of two layers of different materials, inserting a moderator into the reflector to thermalize the neutron beam, and bending the extraction channel to avoid direct extraction of high energy neutrons. Combined reflector system produces 3.2 times higher neutron flux than no reflector when using W and Fe as outer and inner reflectors. The beam convergence is not dependent on reflector materials. Polyethylene (PE) and Fe combination produces fast neutron beam where more than 90% of the neutrons are fast. Combination of PE and D2O produces more than 30% thermalized neutron beam, but it contains epithermal and fast neutrons. When using moderator (D2O), the thickness of which is over 30 cm, more than 90% of the neutrons are thermalized. The bend angle of 20° produces more than 80% thermalized neutron beam. Both inserting moderator and bending channel are effective to extract thermalized neutron beam. These results are useful for designing a neutron source which can produce specified neutron beam.
