Speaker
Description
The tokamak scheme for magnetic confinement of hot plasma requires careful optimization before operations with active fusion grade plasmas. The Con-trolled operations aim to maintain a thermalized state of hot plasma species where generation of fast beam-like population of electron species must be prevented, especially during the disruption events when sudden loss of plasma current induces large toroidal electric field, capable of producing so called run-away electrons. Number of runaway electrons produced during disruption in large tokamaks depends sensitively on the magnetic field strength[1]. The collisionless Whistler mode instability is identified to be preventing
run-away generation in a sub-threshold regime. The whistler growth rate is inversely proportional to magnetic field allowing them to scatter runaways and prevent runaway beams from forming. The phase-space distributions of runaway electrons however remain very complex requiring large scale kinetic-simulations to analyze the scattering process. The 1X-3V fully electromagnetic Vlasov simulations done of the collisionless whistler instability allow the run-away-like beam distributions to be used [2-3]. The simulations address both linear and nonlinear operational regimes of the instability. The limiting regime of marginal propagation of nonlinear whistler instability is also characterized.