Dynamic interaction between a solitary drift wave structure and zonal flows in a linear cylindrical device

Abstract

A solitary drift wave structure and its quasi-periodic change are discovered in a linear magnetized plasma. Detailed investigations show that the periodic changes are accompanied by an emission of splash, that is, a short lifetime event characterized by much higher frequencies than that of the fundamental drift waves. Dynamic interaction between the solitary wave and zonal flows is found to cause the emission of splashes since the splashes occur in a particular phase of zonal flows. The findings should give a deep insight into the dynamics and structural formation of magnetically confined plasmas and rotating planets, which are governed by drift and Rossby waves, respectively.

Identification of Quasi-Periodic Nonlinear Waveforms in Turbulent Plasmas

“…Figure 1 (a) illustrates a time series of observed fluctuations for a floating potential, which was observed in PANTA plasmas [1]. In this case, the perturbation is quasi-periodic, as can be…”

“…Shigeru INAGAKI 1,2) , Yudai MIWA 3) , Tatsuya KOBAYASHI 3) , Takuma YAMADA 4) , Yoshihiko NAGASHIMA 1,2) , Tomohiro MITSUZONO 3) , Hiromitsu FUJINO 3) , Makoto SASAKI 1,2) , Naohiro KASUYA 1,2) , Maxime LESUR 2) , Yusuke KOSUGA 5) , Akihide FUJISAWA 1,2) , Sanae-I. ITOH 1,2) and Kimitaka ITOH A new method is presented for identifying waveforms of fluctuations in turbulent plasmas.…”

“…ITOH 1,2) and Kimitaka ITOH A new method is presented for identifying waveforms of fluctuations in turbulent plasmas. The method is based on heartbeat analysis in which the convolution of a waveform is obtained by employing the phase tracking method.…”

Phenomenological Classification of Turbulence States in Linear Magnetized Plasma PANTA

“…The solitary wave is characterized by a sawtooth-like waveform in the real space and by a significant funda-mental mode and higher order harmonics in the frequency and wavenumber spaces [15]. A dynamic oscillation of nonlinear coupling strength was observed by a local measurement [16,17], which is considered to be a clue to explain the excitation mechanism of the higher harmonics.…”

“…Formation mechanism of the shock front is discussed recently [18]. Dynamic competition between the solitary wave and the zonal flow type oscillation was also studied [15,19,20]. An abrupt and spontaneous transition between the solitary wave state and the streamer state was also observed [21,22].…”