Wavelet analyses using parallel computing for plasma turbulence studies

Fujisawa, A.; Shimizu, A.; Itoh, K.; Nagashima, Y.; Yamada, T.; Inagaki, S.; Matsuoka, K.; Itoh, S.-I.
October 2010
Physics of Plasmas;Oct2010, Vol. 17 Issue 10, p104503
Academic Journal
The wavelet analyses have been carried out, using a cluster of personal computer, on the signal of electric field fluctuations measured with heavy ion beam probes in the compact helical system stellarator. The results have revealed the intermittent characteristics of turbulence and of the nonlinear couplings between elemental waves of turbulence. The usage of parallel computing is found to successfully reduce the calculation time as inversely proportional to the CPU number used the cluster, which shows the nature of 'embarrassingly parallel computation.' The present example of the wavelet analyses clearly demonstrates the importance of the advanced analyzing methods and the parallel computation for the modern studies of plasma turbulence.


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