Excitation of thermonuclear cone instabilities by toroidal equilibrium distributions of high-energy alpha particles in tokamaks

The possibility of a new set of thermonuclear cone instabilities in tokamaks is demonstrated. These instabilities are caused by an inherent anisotropy existing in the alpha-particle velocity distribution function owing to the finite width of the particle orbits in combination with a spatially varying particle source. The conditions for the excitation of shear Alfvén waves by well-trapped alpha particles are studied.