Impact of Energetic Ion Driven Global Modes on Toroidal Plasma Confinements

TOI Kazuo
YAMAMOTO Satoshi
TAKECHI Manabu
NAKAJIMA Noriyoshi
ISOBE Mitsutaka
TAKAGI Shoji
MATSUNAGA Go
OHDACHI Satoshi
SAKAKIBARA Satoru
OSAKABE Masaki
SASAO Mamiko
KOTANI Jyunichi
CHS and LHD Experimental Groups
Kazuo TOI
Satoshi YAMAMOTO
Manabu TAKECHI
Noriyoshi NAKAJIMA
Mitsutaka ISOBE
Shoji TAKAGI
Go MATSUNAGA
Satoshi OHDACHI
Satoru SAKAKIBARA
Masaki OSAKABE
Mamiko SASAO
Jyunichi KOTANI
and LHD Experimental Groups CHS

Publication date

January 2002

Publisher

The Japan Society of Plasma Science and Nuclear Fusion Research

Abstract

Excitation of energetic-ion-driven Alfv6n eigenmodes (AEs) and their impact on energetic ion confinement are widely and intensively studied in helical devices such as CHS and LHD as well as major tokamaks. The excitation of AEs sensitively depends on the parameter space defined by the averaged beam beta and the velocity ratio V6nlV6 (V611 : injected beam ion velocity, Va: Alfv6n velocity). In LHD, these two relevant parameters are widely scanned without suffering from current disruptions. So far, toroidicity induced AE (TAE), global AE (GAE) and energetic particle mode (EPM) or resonant TAE (R-TAE) were identified during tangential neutral beam injection (NBI) in CHS and LHD. Moreover, a new coherent mode with the frequency by about 8 time...