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As Nuclear News has done since 2022, we have compiled a review of the nuclear news that filled headlines and sparked conversations in the year just completed. Departing from the chronological format of years past, we open with the most impactful news of 2025: a survey of actions and orders of the Trump administration that are reshaping nuclear research, development, deployment, and commercialization. We then highlight some of the top news in nuclear restarts, new reactor testing programs, the fuel supply chain and broader fuel cycle, and more.
Kozo Yamazaki, Osamu Motojima, Makoto Asao
Fusion Science and Technology | Volume 21 | Number 2 | March 1992 | Pages 147-160
Technical Paper | Experimental Device | doi.org/10.13182/FST92-A29734
Articles are hosted by Taylor and Francis Online.
Optimization studies have been carried out for the proposed Large Helical Device, which has a major radius of ∼4 m and a magnetic field of ∼4 T, in which a key experiment is to demonstrate a divertor concept. These studies clarified that configurations with a higher helical coil pitch parameter γc (γc ≳ 1.25) and a larger plasma minor radius are not consistent with the requirement of a clean divertor configuration. More compact, lower m systems (m ≲ 8) without helical coil pitch modulation are ruled out by the equilibrium beta limit of the plasma and the stability limit of the superconducting coil current because of the higher maximum magnetic field strength. Systems with a larger aspect ratio and larger m (m ≳ 12, γc ∼ 1.2 to 1.3) with better neoclassical confinement properties are not effective because of a lower stability beta and a narrower clearance between the divertor layer and the wall. An l = 2/m = 10/γc = 1.2 superconducting system is found to be an optimized high-nτT configuration for 4 m/4 T next-generation experiments with respect to the high-beta requirement, clean divertor installation, superconducting coil engineering, and cost optimization.