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Recent surveys confirm high levels of U.S. nuclear support
Surveys have consistently indicated that public support in the United States for the use of nuclear energy has been increasing in recent years. Four recent surveys continue to suggest that near-record-high numbers of Americans support nuclear energy. However, the survey results differ—sometimes widely—in the details of their findings.
Osamu Mitarai, Hiroki Hasuyama, Yoshihisa Wakuta
Fusion Science and Technology | Volume 21 | Number 4 | July 1992 | Pages 2265-2283
Technical Paper | Special Issue on D-He Fusion / D-3He/Fusion Reactor | doi.org/10.13182/FST92-A29720
Articles are hosted by Taylor and Francis Online.
Ignition characteristics in deuterium-tritium (D-T) and D-3He tokamak reactors with spin-polarized fuels are presented by using the ignition access condition based on the generalized saddle point in the representation of . Enhancement of the D-T fusion cross section due to parallel spin polarization with respect to the magnetic field can reduce the confinement enhancement factor required for reaching ignition by ∼20% if fusion particle loss is not induced by the anisotropic fusion particle distribution. Spin polarization is thus effective when a D-T reactor is marginal for ignition. In D-3He fusion, it is more advantageous to use spin-polarized fuel in the heating phase than in the case of D-T fusion. The ignition toroidal beta value can be reduced by spin polarization from 12 ± 0.8 to 5.3 ± 0.5% in D-3He = 2:1 plasma and from 17 ± 0.5 to 6.5 ± 0.2% in D-3He = 1:1 plasma. The auxiliary heating power to reach ignition, which is rather large for D-3He fusion, can be reduced by a factor of 2 to 3 compared with the unpolarized case. For example, in the D-3He Tokamak Reactor, 350 MW of auxiliary heating power for D:3He = 2:1 and Ti(0)/Te(0) = 1 without spin polarization can be reduced to 190 MW with complete polarization of the deuterium and 3He ions. The deuterium-deuterium fusion suppression effect, if it exists, does not alter the ignition condition much. Various problems related to the spin polarization scheme are also discussed.