TY - JOUR
T1 - Bi-coherence analysis of fluctuations with long distance correlation in toroidal plasmas
AU - Inagaki, Shigeru
AU - Kobayashi, Tatsuya
AU - Itoh, Kimitaka
AU - Tokuzawa, Tokihiko
AU - Itoh, Sanae I.
AU - Ida, Katsumi
AU - Tamura, Naoki
AU - Kasuya, Naoyuki
AU - Fujisawa, Akihide
AU - Kubo, Shin
AU - Shimozuma, Takashi
AU - Yagi, Masatoshi
AU - Tanaka, Kenji
AU - Nagayama, Yoshio
AU - Kawahata, Kazuo
AU - Yamada, Hiroshi
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2012/3
Y1 - 2012/3
N2 - Macro-scale temperature fluctuations, which have long radial correlation length (of the order of the plasma radius), have been discovered on Large Helical Device (LHD). In this paper, non-linear coupling between the long-range fluctuations and microscopic fluctuations is investigated using cross bi-coherence analysis. The significant cross bicoherence between long-range fluctuations and micro-fluctuations is observed in the range of frequency f < 100kHz, where f is the frequency of microscopic fluctuations. It is found that the squared bi-coherence and bi-phase for this three-wave coupling is weakly dependent on the frequency of microscopic fluctuations. These observations demonstrate that the microscopic fluctuations are coherently interacting with long-range fluctuations.
AB - Macro-scale temperature fluctuations, which have long radial correlation length (of the order of the plasma radius), have been discovered on Large Helical Device (LHD). In this paper, non-linear coupling between the long-range fluctuations and microscopic fluctuations is investigated using cross bi-coherence analysis. The significant cross bicoherence between long-range fluctuations and micro-fluctuations is observed in the range of frequency f < 100kHz, where f is the frequency of microscopic fluctuations. It is found that the squared bi-coherence and bi-phase for this three-wave coupling is weakly dependent on the frequency of microscopic fluctuations. These observations demonstrate that the microscopic fluctuations are coherently interacting with long-range fluctuations.
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U2 - 10.1143/JPSJ.81.034501
DO - 10.1143/JPSJ.81.034501
M3 - Article
AN - SCOPUS:84863229173
VL - 81
JO - Journal of the Physical Society of Japan
JF - Journal of the Physical Society of Japan
SN - 0031-9015
IS - 3
M1 - 034501
ER -