Formation of core transport barrier and CH-mode by ion Bernstein wave heating in PBX-M

Observation of core transport barrier formation (for particles, ion and electron energies, and toroidal momentum) by ion Bernstein wave heating (IBWH) in PBX-M plasmas is reported. The formation of a transport barrier leads to a strong peaking and significant increase of the core pressure (70%) and toroidal momentum (20%), and has been termed the core high confinement mode (CH-mode). This formation of a transport barrier is consistent, in terms of the expected barrier location as well as the required threshold power, with a theoretical model based on the poloidal sheared flow generation by the IBW power. The use of IBW induced sheared flow as a tool to control plasma pressure and bootstrap current profiles shows a favorable scaling for use in future reactor grade tokamak plasmas. (author). 9 refs, 4 figs