Speaker
Mr
Fumiyoshi Kin
(Kyushu University)
Description
Nonlinearly generated structure and its properties have been studied commonly for general physics. In magnetized plasma, pressure inhomogeneity generates drift waves to form several types of nonlinear waves. In particular, a streamer is known as a nonlinear wave [1] that is important for the plasma confinement. It is because that the streamer has radially elongated structure, thus enhances radial transport. The streamer was found in a linear plasma device, PANTA, for the first time, and to be produced through the couplings between drift waves and low frequency fluctuations, namely mediator [2].
Recently, we have succeeded in extracting the precise structure of nonlinear wave of streamer and mediator using the conditional averaging. It is found that the degree of localization increases with the amplitude of the streamer and mediator, which is in agreement with the nonlinear property of soliton. Moreover, as is shown in Fig. 1, the two-dimensional structure of the streamer envelope is reconstructed. This talk discusses the newly obtained nonlinear characteristics and two-dimensional spatial structure of streamer and mediator.
Figure 1 : Reconstructed 2-dimensional structure of streamer envelope.
References
[1] S. Champeaux et al., Phys. Lett. A 288, 214 (2001)
[2] T. Yamada et al., Nature Phys. 4, 721 (2008)
Primary author
Mr
Fumiyoshi Kin
(Kyushu University)
Co-authors
Prof.
Akihide Fujisawa
(Kyushu University)
Dr
Hiroyuki Arakawa
(Shimane University)
Mr
Kazunobu Hasamada
(Kyushu University)
Prof.
Kimitaka Itoh
(Chubu University)
Dr
Kotarou Yamasaki
(Kyushu University)
Dr
Makoto Sasaki
(Kyushu University)
Dr
Naohiro Kasuya
(Kyushu University)
Prof.
Sanae Itoh
(Kyushu University)
Prof.
Sigeru Inagaki
(Kyushu University)
Dr
Takuma Yamada
(Kyushu University)
Dr
Tatsuya Kobayashi
(National Institute for Fusion Science)
Dr
Yoshihiko Nagasima
(Kyushu University)
Dr
Yusuke Kosuga
(Kyushu University)
