Study on impurity hole plasmas by global neoclassical simulation

An impurity hole observed in the Large Helical Device (LHD) is a hollow density profile of an ion species formed core plasma where negative (inward-pointing) ambipolar radial electric field ($E_r$) exists. Although local neoclassical models have predicted sign $E_r$ plasmas for entire minor radius, experimental measurement has shown that changes from to positive along radius. In present work, we investigate transport using global simulation code FORTEC-3D. The variation electrostatic potential on flux surface ($\Phi_1$) evaluated quasi-neutrality condition multi-ion-species by simulation. and fluxes are determined solving drift-kinetic equation including effect $\Phi_1$. By simulation, show which radius obtained as solution with such $E_r$, carbon can be outwardly directed even $E_r<0$ around magnetic axis. Furthermore, it found outward only factor 2-3 balancing modeled inward turbulent flux. Our result indicates moved one step closer reproducing kinetic