Dynamical Phenomena in Plasma Wave Systems

1.阐明了离子束和电子束等离子体中孤子的性质和在不稳定波非线性发展中的作用。孤子的形成起到了稳定不稳定性的作用，实验证实了这一点。作为一种新的粒子加速机制，提出了大振幅磁声波共振加速机制。这一机制解释了太阳耀斑中粒子的快速加速现象。利用导数的非线性薛定谔方程研究了沿磁通传播的非线性Alfven波。得到了初始条件与出现孤子个数之间的关系。利用双等离子体装置，观察到泵浦波的周期倍增和电子等离子体波的高次谐波产生等混沌现象。考虑含耗散项的非线性薛定谔方程，阐明了微扰下多孤子态的性质。采用漂移波的涡丝近似，研究了涡丝的动力学和统计特性。解析地得到了旋涡的扩散常数。提出了由孤子理论构造新的链节多项式的一般理论。链节多项式给出了一种对节点和链节进行分类的系统方法。研究了漂移波在非均匀磁化等离子体中的传播和激发。观察到具有Sbliton特性的漂移脉冲波。研究了离子声波孤子的反射和传输。开发了产生大幅度离子波的技术。对于回旋运动的粒子，施加垂直于磁场的静电波。数值模拟表明，在相空间中形成了一个薄的随机层。

1. Properties and roles of solitons in the nonlinear development of unstable waves were clarified for ion beam and electron beam plasmas. Formation of solitons works to stabilize the instability, which was confirmed by experiments.2. As a new mechanism of particle acceleration, resonant acceleration by large amplitu magneto-sonic waves was proposed. Rapid particle acceleration in solar flares is explained by this mechanism.3. Nonlinear Alfven waves propagating along magnetic flux was investigated by using the derivative nonlinear Schrodinger equation. Relations between initial conditions and numbers of emerging solitons were obtained.4. Using double plasma device, chaos phenomena such as period doubling of pump waves and higher harmonics generation of electron plasma waves were observed.5. Considering the nonlinear Schrodinger equation with a dissipative term, properties of multi-soliton states under the perturbations were clarified.6. Employing vortex filament approximation for drift waves, dynamical and statistical properties of vortex filaments were investigated. Diffusion constant for vortices was analytically obtained.7. A general theory to construct new link polynomials from soliton theory was proposed. Link polynomials give a systematic method to classify knots and links.8. Propagations and excitations of drift waves in non-uniform magnetized plasmsas were investigated. Drift pulse waves, which have sbliton properties, were observed.9. Reflections and transmissions of ion sound wave solitons were studied. Techniques for the creation of large amplitude ion waves were developed.10. To the particle under cyclotron motion, a static electric wave perpendicular to the magnetic field is applied. Formation of a thin stochastic layer in phase space was shown numerically.