Gyrokinetic study of slowing-down α particles transport due to trapped electron mode turbulence

Transport of α particles due to trapped electron mode (TEM) turbulence is investigated from nonlinear and quasilinear gyrokinetic simulations. We consider both slowing-down and Maxwellian distribution functions for α particles and identify and compare diffusive and convective parts of α particle transport as a function of the α particle's energy normalized to the background plasma temperature. We find that TEM induces much lower transport of energetic α particles such as fusion products than that of thermal Helium ions in the trace limit. This disparity from our study is found to be even greater than that reported previously for the ion temperature gradient mode [C. Angioni and A. G. Peeters, Phys. Plasmas. 15, 052307 (2008)].