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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fusion Science and Technology
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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
M. Yokoyama, H. Maassberg, C. D. Beidler, V. Tribaldos, K. Ida, F. Castejón, T. Estrada, A. Fujisawa, T. Minami, T. Shimozuma, Y. Takeiri, J. Herranz, S. Murakami, H. Yamada
Fusion Science and Technology | Volume 50 | Number 3 | October 2006 | Pages 327-342
Technical Paper | Stellarators | doi.org/10.13182/FST06-A1254
Articles are hosted by Taylor and Francis Online.
The characteristics of core electron-root confinement (CERC) in helical devices are illustrated using results from four different experiments: the Compact Helical System, Large Helical Device, TJ-II, and Wendelstein 7-AS. Common features include strongly peaked electron temperature profiles and large positive radial electric fields Er in the core region for discharges with sufficient central electron cyclotron heating (ECH). Such observations are consistent with a transition to the electron-root solution of the ambipolarity condition for Er, a feature of neoclassical theory that is unique to nonaxisymmetric configurations. The magnetic topology of the configuration plays a role in this transition, and thresholds are found for the particle density and ECH power, in accordance with neoclassical expectations. Neoclassical theory alone cannot explain all observations, however, as CERC formation can also be influenced by ECH-driven convective fluxes of localized electrons and by the presence of magnetic islands in the core region. This is the first report describing collaborative activities within the framework of the International Stellarator Profile Data Base.