TJ-II: Evolution of LCR by HIBP and Probes: Difference between revisions

It is believed that the anomalous transport in toroidal devices (tokamaks and stellarators) has a turbulent nature. Turbulence has a very complicated structure, containing the self-regulating mechanism - Zonal Flow (ZF) - poloidally and toroidally symmetric plasma structures intertwinned with dynamic of turbulent eddies <ref>P.Diamond et al, PPCF 2005(2017)</ref>. Manifestation of the ZF is the Long-range correlations (LRC), observed in both plasma edge by dual probes <ref>Pedrosa et al, NF 2008</ref> and plasma core by Dual HIBP <ref>[Melnikov et al NF 2017]</ref>.

Perturbation of the plasma density and temperature profiles after Pellet Injection (PI) in ECRH and NBI plasmas, specifically during PIEC (NBI) will allow us to follow the evolution of the plasma turbulence, LRC and plasma potential in the transient regimes from normal to enhanced confinement and back. Such simultaneous measurements has a strong potential to shed a new light to the physical mechanism of the turbulent transport reduction in case of PIEC (NBI) compared to density evolution without confinement enhancement (PI in ECRH).