Wavelet analysis of the parameters of edge plasma fluctuations in the L-2M stellarator

9th International Conference on Modern Techniques of Plasma Diagnostics and their Application

Maslov, S.A.^1 ; Vasilkov, D.G.^2 ; Kholnov, Yu V.^2 ; Skvortsova, N.N.^2,3

Joint Institute for High Temperatures of the Russian Academy of Sciences (JIHT RAS), Izhorskaya st. 13 Bd.2, Moscow

125412, Russia^1

A.M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilova Street 38, Moscow

119991, Russia^2

National Research Nuclear University MEPhI, Kashirskoe shosse 31, Moscow

115409, Russia^3

关键词: Analytical calculation;    Fast transition;    Morlet Wavelet;    Parameter changes;    Sharp increase;    Spectral fluctuations;    Temporal structures;    Time interval;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/666/1/012009/pdf
DOI  :  10.1088/1742-6596/666/1/012009

来源: IOP

【 摘 要 】

Wavelet analysis results are presented for evolution of the spectral fluctuation characteristics of the edge plasma density and potential in the L-2M stellarator for fast and slow transport transitions. The fast transition comes out as a sharp increase of the energy and electron density within ∼0.1ms and the slow one as a weak parameter change during a 0.5 to 1 ms time interval. It is shown that the use of the "Mexican hat" and Morlet wavelets allows one to detect the moment of the fast transition, whereas applying the Haar wavelet adds to this also an estimate of its duration, conforming to the analytical calculations, and reveals the temporal structure of the slow transition.