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Fusion Science and Technology
July 2025
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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.
K. Oki, A. Sanpei, H. Himura, S. Masamune
Fusion Science and Technology | Volume 63 | Number 1 | May 2013 | Pages 386-388
doi.org/10.13182/FST13-A16963
Articles are hosted by Taylor and Francis Online.
Dependence of several properties of Quasi-Single-Helicity (QSH) states on field reversal parameter F is investigated in low-aspect-ratio reversed-field-pinch (RFP) machine RELAX. QSH probability with dominant n = 5 or 6 (n is toroidal mode number) is higher in low F region than high F. QSH probability and duration with dominant n = 3 or 4 are higher in high F region. These suggest change of innermost resonant n with F as shown in an equilibrium reconstruction. QSH probability, duration and dominant mode amplitude with the dominant mode of possible innermost resonant n = 3, 4 or 5 are higher than other n, which is desirable for improved confinement. Averages of the spectral index NS for flat-topped plasma current phases are similar to that predicted by a simulation which has shown NS is lower as aspect ratio is lower. This agreement and the higher QSH probability of 2 - 3 % than another high aspect ratio RFP machine may show advantage of the low aspect ratio RFP in achieving QSH.
