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Fusion energy: Progress, partnerships, and the path to deployment
Over the past decade, fusion energy has moved decisively from scientific aspiration toward a credible pathway to a new energy technology. Thanks to long-term federal support, we have significantly advanced our fundamental understanding of plasma physics—the behavior of the superheated gases at the heart of fusion devices. This knowledge will enable the creation and control of fusion fuel under conditions required for future power plants. Our progress is exemplified by breakthroughs at the National Ignition Facility and the Joint European Torus.
Yuji Nakamura, N. Nakajima, K. Y. Watanabe, M. Yokoyama
Fusion Science and Technology | Volume 50 | Number 2 | August 2006 | Pages 281-286
Technical Paper | Stellarators | doi.org/10.13182/FST06-A1247
Articles are hosted by Taylor and Francis Online.
Effects of the bumpy field component on the bootstrap current in the low-collisionality regime are discussed for L = 1 helical plasmas. It is usually considered that the bumpy field component or toroidal mirror ratio suppresses the bootstrap current in helical plasmas since it is a symmetry-breaking component. In the Heliotron J device, however, it has been observed that the direction of the bootstrap current can be changed according to the magnitude of the bumpy field component. In this study, we calculate the bootstrap current in the low-collisionality regime using a model magnetic field spectrum and discuss the condition under which the reversal of the bootstrap current direction occurs.