https://doi.org/10.1051/epjconf/201714701002
A Kinetic Study of Microwave Start-up of Tokamak Plasmas
1 York Plasma Institute, Department of Physics, University of York, York, YO10 5DD, UK
2 Culham Centre for Fusion Energy, Abingdon, OX14 3DB, UK
a e-mail: ejdt500@york.ac.uk
Published online: 24 July 2017
A kinetic model for studying the time evolution of the distribution function for microwave startup is presented. The model for the distribution function is two dimensional in momentum space, but, for simplicity and rapid calculations, has no spatial dependence. Experiments on the Mega Amp Spherical Tokamak have shown that the plasma current is carried mainly by electrons with energies greater than 70 keV, and effects thought to be important in these experiments are included, i.e. particle sources, orbital losses, the loop voltage and microwave heating, with suitable volume averaging where necessary to give terms independent of spatial dimensions. The model predicts current carried by electrons with the same energies as inferred from the experiments, though the current drive efficiency is smaller.
© The Authors, published by EDP Sciences, 2017
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