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Russia withdraws from 25-year-old weapons-grade plutonium agreement
Russia’s lower house of Parliament, the State Duma, approved a measure to withdraw from a 25-year-old agreement with the United States to cut back on the leftover plutonium from Cold War–era nuclear weapons.
Osamu Mitarai, Akira Hirose, Harvey M. Skarsgard
Fusion Science and Technology | Volume 20 | Number 2 | September 1991 | Pages 208-221
Technical Paper | Plasma Engineering | doi.org/10.13182/FST91-A29691
Articles are hosted by Taylor and Francis Online.
The ignition access condition is described based on the operation path and the saddle point in the generalized ignition contour map . With a confinement scaling law such as for the energy confinement time in terms of the net input heating power density, as employed in most Plasma Operation Parameter Contour (POPCON) analyses, where τE,L is the L-mode confinement time and Cop is the constant parameter, the ignition access condition is given by , where is the height of the generalized saddle point. The height of the generalized saddle point for various arbitrary plasma parameters enables a reactor designer to look at the overall behavior of a reactor. The confinement enhancement factor γH is determined relative to the L mode, which is required for reaching ignition in a tokamak or stellarator reactor. This operation path method is compared with the POPCON approach, and the relative merits of each are discussed.