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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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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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
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Christmas Night
Twas the night before Christmas when all through the houseNo electrons were flowing through even my mouse.
All devices were plugged in by the chimney with careWith the hope that St. Nikola Tesla would share.
Mitsushi Abe,* Akira Doi, Kazuhiro Takeuchi, Michio Otsuka, Shigeyoshi Kinoshita, Satoshi Nishio, Masayoshi Sugihara, Ryuji Yoshino
Fusion Science and Technology | Volume 32 | Number 4 | December 1997 | Pages 545-560
Technical Paper | Special Section: Plasma Control Issues for Tokamaks / Plasma Engineering | doi.org/10.13182/FST97-A19904
Articles are hosted by Taylor and Francis Online.
Tokamak startup characteristics with a low-loop-resistance vacuum vessel were studied in the HT-2, which is a tokamak with a major radius of 41 cm, a minor radius of 11 cm, and a plasma current of IP < 55 kA. Precise poloidal magnetic field control is possible using independently and multivariably controlled poloidal field coils. The vacuum vessel loop resistance Ωv was originally high (14 mΩ), but it was modified to be able to operate with a low value (0.3 mΩ). The latter is approximately one-tenth of the plasma resistance (2.2 mΩ) at breakdown (Te = 10 eV). With Ωv = 0.3 mΩ, the magnetic field induced by the eddy current is large, and it disturbs the breakdown. However, careful compensation of the poloidal field makes a well-controlled ohmic startup possible. Other results are as follows: very little difference in the consumed ohmically heated flux was observed between discharges with low and high loop resistances; well-controlled startup was obtained with a very low loop voltage of 2.5 V, which corresponded to the 1 V/m electric field; the breakdown condition is well described by the electron avalanche model. It is concluded that low Ωv is applicable to a tokamak design, as long as the poloidal magnetic field is well controlled even during the breakdown phase.