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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.
V. Ya. Goloborod'ko, Ya. I. Kolesnichenko, S. N. Reznik, V. A. Yavorskij
Fusion Science and Technology | Volume 25 | Number 3 | May 1994 | Pages 249-257
Technical Paper | Alpha-Particle Special / Plasma Engineering | doi.org/10.13182/FST94-A30281
Articles are hosted by Taylor and Francis Online.
A kinetic equation is derived for the neoclassical distribution function of alpha particles with orbits intersecting or approaching the magnetic axis of a tokamak. This equation takes into account both the collisional slowing down and the pitch-angle scattering of alpha particles. An equation with a simplified pitchangle scattering term is solved analytically, and the distribution function obtained is used to find the alpha-particle bootstrap current at the magnetic axis. It is shown that the pitch-angle scattering leads to an alpha-particle current in the near-axis region that is larger than the one predicted from early neoclassical theory, which allows only for the slowing down of alpha particles.