SATO Tetsuya NIFS, Theory Professor, 教授 (80025395)
SAWA Takeyasu Aichi U. of Edu. Assoc. Professor, 教育学部, 助教授 (90111864)
MATSUMOTO Ryoji Chiba U. Assoc. Professor, 教養部, 助教授 (00209660)
UCHIDA Yutaka Tokyo U., Astron. Professor, 理学部, 教授 (90012814)
HANAWA Tomoyuki Nagoya U., Phys. Research Assoc., 理学部, 助手 (50172953)
|Budget Amount *help
¥5,800,000 (Direct Cost : ¥5,800,000)
Fiscal Year 1992 : ¥1,800,000 (Direct Cost : ¥1,800,000)
Fiscal Year 1991 : ¥4,000,000 (Direct Cost : ¥4,000,000)
The purposes of this project are to organize cooperative research on various magnetohydrodynamic phenomena (reconnection, dynamo, MHD turbulence, MHD wave, jet, accretion, etc.) observed in many active celestial objects, and to encourage active communication between researchers, who are studying similar physical processes, in different fields (e.g., astronomy, nuclear fusion, plasma physics, geophysics, fluid mechanics).
In order to accomplish these objectives, we held a symposium on cosmic MHD phenomena at Atami in September, 1992. More than 60 people attended. We discussed not only theoretical research results but also observational results in relation to various cosmical plasmas ranging from fusion plasmas to intergalactic plasmas. Specific items we discussed are; dynamo processes in fusion plasmas, convection and dynamo in terrestrial and planetary cores, vortex reconnection, magnetic reconnection and Kelvin-Helmholtz instability in terrestrial magnetosphere, acceleration and dynami
cs of solar wind, magnetohydrodynamic phenomena in the Sun (especially on magnetic reconnection and dynamic phenomena in the solar corona observed by YOHKOH), jet formation in black hole magnetosphere, magnetic field in star forming regions, MHD phenomena in interstellar space, intergalactic magnetic fields, etc.
Major results obtained by these researches are summarized in the following;
(1) We compared magnetic reconnections occurring in the tail of terrestrial magnetosphere and in the solar corona, and found that the formation and acceleration of plasmaids play a key role in both cases. This has also been confirmed by 2D and 3D MHD numerical simulations of magnetic reconnection for both terrestrial and solar cases.
(2) Various dynamic phenomena (loops, jets, spincules) similar to solar coronal dynamic phenomena have been discovered in disk galaxies from detailed comparison between solar coronal images taken by YOHKOH and high resolution optical images of disk galaxies. Numerical simulations have also been done for the Parker instability both in disk galaxies and in the Sun, which explains the formation of magnetic loops in disk galaxies and the Sun. Less