@article{beb672537129469d9001c54536c2f088,

title = "Convergence study of bispectral analysis in experiments of high temperature plasmas",

abstract = "A convergence study of bispectral analysis on toroidal plasma turbulence is presented with a theoretical estimate of bicoherence for the system of the drift wave and zonal flow. Examples are chosen from the analysis of floating potential fluctuation in the edge region of the JFT-2M tokamak. The convergence properties of the bispectral functions are clarified for an oscillatory branch of zonal flow (or geodesic acoustic mode) and drift waves. The total squared bicoherence or the biphase converges inversely proportional to the realization number or to the square root of the realization number, respectively. The numbers of realizations to qualitatively converge and obtain a quantitatively significant value of bicoherence are discussed for the drift wave fluctuations and for the zonal flow.",

author = "Y. Nagashima and Itoh, {S. I.} and M. Yagi and K. Itoh and A. Fujisawa and K. Hoshino and K. Shinohara and K. Uehara and Y. Kusama and A. Ejiri and Y. Takase",

note = "Funding Information: The authors are grateful to Dr. T. Ido, Professor A. Fukuyama, and Professor P. H. Diamond for useful discussions. This work was partially supported by Grant-in-Aid for Specially Promoted Research (16002005) of MEXT, Japan, by the 4-2-4 program of Kyushu University, by the collaboration programs of National Institute for Fusion Science as well as Research Institute for Applied Mechanics, Kyushu University, and by the collaboration program between the University of Tokyo and Fusion Research and Development Directorate of JAEA. The authors also appreciate the support of all members of the JFT-2M group in carrying out the experiment. ",

year = "2006",

doi = "10.1063/1.2194016",

language = "English",

volume = "77",

journal = "Review of Scientific Instruments",

issn = "0034-6748",

publisher = "American Institute of Physics Publising LLC",

number = "4",

}