Simulation study of self-organization in plasma

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We have investigated the detail of "Self-organization" phenomena in various spatial scale in collaboration with the people in U.S., Europe and Australia.The followings are some of the successful results we got in this research project.1) We have developed a new simulation code in order to reveal the dynamo mechanism in MHD plasma.We found that the convection motion of the rotating plasma makes a cell structure and forms a dipole magnetic field through the transformation of the kinetic energy to the magnetic energy.It should be emphasized that the magnetic reconnection plays an important role in the formation of the dipole magnetic field structure.2) We have studied the structure of the finite beta plasma in the helical system and found the following interesting and important self-organization process.Even if the helical plasma is initially unstable and the structure is destroyed due to the pressure driven instability, the ordered structure is formed again through the nonlinear interact … More ion.It should be noticed that when the structure is formed, the entropy, i.e., thermal energy is generally produced.In this case, the thermal energy is the cause of the structure instability, and simultaneously it resulted in the ordered structure.3) We have developed a quite new particle simulation code for an open boundary system.We found the "Super" ion-Acoustic double layr whose amplitude is more than 20 times larger than the regular one.In this study, it can be pointed out that the entropy production rate becomes highest when the structure is made up, and the entropy expulsion mechanism plays an important role in the maintenance of the ordered structure.4) We alomost made up a general scenario of the self-organization process for MHD plasmas.One of the conclusion of this scenario is that the structure formation occurs intermittently and shows the recurrence depending on the way of energy input to the system.Besides above results, we have studied various self-organization processes such as the structure formation in a dusty plasma, or the crystallization of polymer in the liquid.Now, we continue this investigation aiming the construction of the general theory of "Self-organization". Less