Collaborative Research: Vlasov Multi-Dimensional Simulation of Langmuir Wave Collapse and Stimulated Raman Scatter in the Fluid-Kinetic Transition Regime

该奖项使弗拉索夫多维（VMD）模型在非平衡等离子体动力学的基本现象的发展和应用。VMD模型利用定向等离子体波湍流特性，在实验室和空间环境中遇到的，通过严格加入粒子和流体方面的等离子体动力学，这是以前无法实现的。人们认为，明确纳入流体动力学的模型必须忽略高温等离子体动力学的基本方面。VMD模型表明，这并不一定是事实，从而推进了我们的理解，显示了在标准等离子体模型中什么是必要的，什么是不必要的。VMD导致了比传统PIC（“粒子单元”）方法更有效的模拟方法。一个早期的研究目标是验证VMD模型与先前通过PIC模拟获得的结果进行比较。VMD模型的验证将允许其应用于预测自然发生在高温等离子体中的等离子体波的非线性演化，如在地球电离层中发现的等离子体附近，以及更接近地球，因为它们发生在实验室产生的等离子体中的强微波和激光脉冲的传播中。 特别重要的是更准确地模拟政权更迭。例如，在等离子体波湍流阻止激光传播之前，可以传输多少功率？ 非物理噪声可能会使PIC模拟确定区域变化边界处的激光强度变得模糊。VMD方法是无噪声的，扩大了等离子体动力学模拟的范围。

This award enables development and application of the Vlasov Multi-Dimensional (VMD) model to fundamental phenomena in non-equilibrium plasma dynamics. The VMD model takes advantage of directed plasma wave turbulence properties, encountered in laboratory and space environments, by rigorously joining particle and fluid aspects of plasma dynamics, something which has previously been unattainable. It had been thought that models which explicitly incorporate fluid dynamics must omit essential aspects of high temperature plasma dynamics. By showing that this is not necessarily the case, the VMD model advances our understanding, showing what is and what is not essential in standard plasma models.VMD results in vastly more efficient simulation methods than afforded by traditional PIC ("particle in cell") methods. An early research goal is validation of the VMD model by comparison with results previously obtained by PIC simulations. Validation of the VMD model will allow its application to predicting the nonlinear evolution of plasma waves that naturally occur in high temperature plasma as found in the neighborhood of pulsars, in the earth's ionosphere, and, closer to earth, as they occur in the propagation of intense microwave and laser pulses in laboratory generated plasma. Of particular importance is the more accurate modeling of regime change. For example, how much power can be transmitted before plasma wave turbulence blocks laser propagation? Determination of laser intensity at regime change boundaries by PIC simulation may be obscured by unphysical noise. The VMD method is noise free, expanding the scope of plasma dynamics accessible by simulation.