IBW heating experiments in HT-7 tokamak

Abstract

The Experiments with Ion Berstein wave (IBW) heating has been carried out in HT-7 superconducting tokamak. Core electron heating and peaking profile of electron temperature can be observed in the beginning 40 ms after injection of IBW. The temporary heating efficiency of IBW increases with the toroidal magnetic field (BT). The electron temperature drops gradually with the increasing electron density after 40 ms of IBW. The electron density increases by a factor up to 2.4 and the profile of electron density becomes wide. Improved particle confinement induced by IBW is one reason for the density increase. Impurity release during IBW heating is also a contribution for the density increase. Suppression of MHD by IBW is also observed. The fluctuation and transport in the SOL of HT-7 tokamak have been investigated using a Langmuir probe array. The polodial shear flow induced by IBW maybe the reason for improved particle confinement.