Role of Alfv?n Instabilities in Energetic Ion Transport

Abstract

Experiments of plasma heating at the ion cyclotron resonance of a minority specie have shown that the heating efficiency degrades above a certain power threshold. It is found that this threshold is due to the destabilization of a branch of shear AlfvŽn waves which causes a diffusive loss of fast ions, the Energetic Particle Modes. These modes not only play a fundamental role in the transport of the fast ions, but appear closely related to the formation of the giant sawteeth.

Long pulse enhanced confinement discharges in the HT-7 superconducting tokamak by ion Bernstein wave heating and lower hybrid wave current drive

“…IBW could act strongly with electrons via ELD near the resonant layer because of the significantly reduced phase velocity, which causes strong modification of the electron distribution function. 17 The peak in the radial profile of I HX in LHCD and IBW-heated plasma is correlated with the region around the 5/2⍀ D (Ϫ0.6a) resonant layer, implying that the incoming LHW can damp on the tail of the modified electron distribution function due to IBW injection and create localized current channels.…”

“…The local synergetic behavior of LHW and IBW was experimentally studied in the Princeton Beta Experiment ͑PBX͒ tokamak. 17 The key issue for achieving high performance discharge by using LHCD and IBW is to increase the high confinement volume. For this purpose, offaxis current drive is utilized to obtain an internal transport barrier ͑ITB͒-like structure beyond the half radius.…”

Patents, Knowledge Governance and Gender

“…Along with gender, it depends on race, socio-economic background, environment, exposure to innovation growing up, and role models. 113 Those born into more affluent families, surrounded by invention and innovation, are more likely to patent later in life. The endowed become further endowed.…”