地球的太空環境自1000 公里以上至整個太陽系邊際充滿所謂的”無碰撞”的完全解離氣體--電漿，其主要成份為電子與質子，特性為高溫、低密度且”磁化＂，磁場之產生與演化因此是太空科學家有興趣研究的重要議題。此無碰撞太空電漿環境可孕育許多有趣的、實驗室無法複製與觀測與量測到的各種時間與空間尺度之電漿現象與特性，如電流片與非線性電漿波的形成與演化。太空電漿物理不僅是重要與具挑戰的基礎科學研究，且有實際應用的重要性，如太陽風與地球磁層的交互作用與帶電粒子及電磁場如何經由磁層頂電流片進入磁層，並儲存於磁尾電流片，最後傳輸至近地球的太空環境是重要的太空電漿物理與太空天氣之研究主題。過去幾年在國科會計畫的支持下，我們在多項的太空電漿物理研究領域，如非熱力平衡電漿、磁化電漿電流片與非線性電漿物理及磁層頂與磁尾的結構與動力等研究，有重要成果與貢獻。本三年期之研究計畫，將應用磁流體力學理論與電漿微觀動力論，結合數值模擬與人造衛星資料等，探討兩大重要之太空電漿物理研究主題。(一) 大尺度磁化電漿電流片的物理，其應用為地球磁層頂與磁尾及太陽與行星際空間等之薄電流片。我們將以磁流體力學理論分析低頻電漿波在電流片中之傳播與特性及分析電流片之穩定性，尤其是電漿之非熱力平衡效應，並應用磁流體及微觀粒子模式探討磁重連的過程。我們也將分析人造衛星資料，結合理論模式，研究地球磁層頂電流片之結構，與建立磁重連發生之統計模式。(二) 非線性電漿波之理論研究，其應用為太陽風、行星際空間與磁層等。我們將應用磁流體及微觀動力理論與模擬探討孤立波、磁洞、震波與磁管等之結構、生成與演化等 Earth’s space environment above 1000 km from the Earth to the edge of the solar system is permeated nearly with collisionless ionized gas – plasma which consists of primarily electrons and ions (protons etc.). One of the major characteristics associated with collisionless space plasmas is its extremely low number density which could not possibly be produced in the laboratory. In addition space plasma is intrinsically magnetized that the generation and evolution of large scale magnetic field is of great interest to space scientists. Due to the lack of collisions many interesting plasma phenomena with wide range of temporal and spatial scales such as the formation of thin current sheets and nonlinear plasma waves etc. may develop which can only be observed by in-situ measurement of spacecraft. Studies of collisionless space plasmas are not only of fundamental and challenging research but also have important applications. Indeed the topics of how the solar wind particles at the magnetopause current may find ways to enter into the magnetosphere, then be stored in the magnetotail in the form of thin current and transported to the near-Earth space environment are one of the major issues of space plasma physics as well as space weather. Under the support of National Science Council grants we have made several important discoveries and contributions to space plasma physics in the past few years, including nonthermal plasma physics, the structure and dynamics of thin current sheet as well as nonlinear plasma waves and instabilities etc. The proposed three-year research project will focus on two major important problems of space plasma physics by utilizing the magntohydrodynamic (MHD) and kinetic theories along with modeling、 numerical simulations as well as data analyses etc. (1) The physics of large-scale magnetized plasma current sheet with the applications to magnetopause and magnetotail currents、solar plasma and interplanetary space etc. In particular, we will study the propagation of low-frequency plasma wave in thin current sheet and analyze its stability due to the nonthermal effect as well as study the magnetic reconnection based on MHD and particle simulations. The structure and dynamics of magnetopause currents in terms of magnetic reconnection will also be studied systematically by analyzing the satellite data. (2) The physics of nonlinear plasma waves with the applications to the solar wind、interplanetary space and magnetosphere etc. The structure、formation and evolution of solitary waves、magnetic holes、shock waves and magnetic flux tubes/ropes etc. will be studied based on fluid and kinetic theories as well as numerical simulations. 研究期間：10008 ~ 10107
