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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.
John C. Wesley, the U. S. ITER Home Teama
Fusion Science and Technology | Volume 21 | Number 3 | May 1992 | Pages 1380-1388
International Thermonuclear Experimental Reactor | doi.org/10.13182/FST92-A29916
Articles are hosted by Taylor and Francis Online.
Design features and performance parameters for HARD — the high-aspect-ratio (A = 4) International Thermonuclear Engineering Reactor (ITER) design variant developed by the U. S. ITER Team — are presented. The HARD design makes it possible for ITER to achieve both the ignition/extended-burn and the steady-state/technology-testing performance goals set forth in the ITER Terms of Reference. These performance capabilities are obtained in a device that is otherwise similar in concept, size and cost to the low-aspect-ratio (A = 2.8) ITER design defined during the ITER Conceptual Design Activity (CDA). HARD is based on the same physics and engineering guidelines as the CDA design and achieves the same ignition performance (ignition margin evaluated against ITER-89P confinement scaling) with inductively-driven plasmas as ITER CDA, but with much greater margin for inductive sustainment of the pulse duration. With non-inductive current drive, HARD operates at lower plasma current and higher plasma density and bootstrap current fraction than ITER CDA, is less constrained by beta limit and divertor considerations, and has increased peaking of the neutron wall load at the test module location. These factors give HARD a much better potential than ITER CDA to achieve the steady-state operation and 1 MWa/m2 technology-testing fluence goals of the ITER objectives.