Density clamping or pump-out phenomena is observed both in tokamaks and helical systems during additional heating, particularly high power density heating as electron cyclotron resonance heating (ECRH). Enhanced electron convective flux induced by a perpendicular acceleration of electrons is one of the candidates of the mechanism of these phenomena. The mechanism of the enhancement of the electron flux is investigated experimentally by comparing the density profile evolutions due to second harmonic X (X2) mode ECRH at the ripple top and bottom. The result suggests that ECRH-induced electron flux is one of the dominant mechanisms of density clamping, which can be used as a powerful tool for controlling the particles and the heat transport.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics