Collective backscattering of gyrotron radiation by small-scale plasma density fluctuations in large helical device.
A version of the collective backscattering diagnostic using gyrotron radiation for small-scale turbulence is described. The diagnostic is used to measure small-scale (k(s) approximately 34 cm(-1)) plasma density fluctuations in large helical device experiments on the electron cyclotron heating of plasma with the use of 200 kW 82.7 GHz heating gyrotron. A good signal to noise ratio during plasma production phase was obtained, while contamination of stray light increased during plasma build-up phase. The effect of the stray radiation was investigated. The available quasioptical system of the heating system was utilized for this purpose.
Kharchev
Nikolay
N
A.M. Prokhorov General Physics Institute, Vavilova 38, 119991 Moscow, Russia. khar@fpl.gpi.ru
Tanaka
Kenji
K
Kubo
Shin
S
Igami
Hiroe
H
Batanov
German
G
Petrov
Alexandr
A
Sarksyan
Karen
K
Skvortsova
Nina
N
Azuma
Yoshifumi
Y
Tsuji-Iio
Shunji
S