利用粒子網格法(Particle-in-Cell法)模擬正電離子聲震波。探討並分析磁聲震波和正電離子聲震波的差別。此外還以馬赫數和密度不連續性為基準去討論正電離子聲孤立波和正電離子聲震波的差別。討論了利用網格法模擬的結果，第一，建立了Langmuir wave動力學的基準，第二，在網格法模擬中加入正電離子來產生正電離子聲波。基於基準，在初始速度中加入了飄移速度，且飄移速度超過聲速。利用KdV方程式去對非線性和分散作用進行了討論而在粒子網格法模擬中也作了同樣的分析。在產生震波的部分，我們利用電漿鞘來當邊界，且利用兩種方法來產生密度不連續性和正電離子聲震波。其中一個方法是通過利用電漿鞘來反射正電離子，而另一個方法是利用兩道正電離子束打向相反方且對著彼此。而在這個研究中我們專注在電場的詳細生成機制和粒子的加速機制，用來了解那些在破壞性的太陽事件中帶電粒子的加速方式。

Ion acoustic shock waves by self-consistent Particle-in-Cell (PIC) simulation is studied. The difference and the analogy between magnetosonic shock waves and ion acoustic shock waves are discussed. Furthermore, the threshold between ion acoustic solitons and the shock waves is discussed in terms of Mach number and density discontinuities. The PIC simulation results are discussed, first for the benchmark of Langmuir wave dynamics, and second for ion acoustic wave dynamics by incorporating ions into the PIC code. Based on the benchmark, initial drift velocity of ions which exceeds the sound speed is incorporated. Employing KdV equation, roles of the nonlinearity and dispersion is discussed which is also revisited in PIC simulation. For the shock generation, we take advantage of plasma sheath near a fixed boundary. Two methods to create the density discontinuity and generate the ion acoustic shocks are taken. One is by utilizing the sheath and reflected ions, and the other is by collision of two ion beams moving in the opposite directions. We focus on the detailed generation mechanism of the electric field, and particle acceleration mechanism in this study, aiming at understanding of charged particle acceleration observes at disruptive solar events.

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