论文标题
基准测试磁化的三波耦合，用于激光反向散射：分析解决方案和动力学模拟
Benchmarking magnetized three-wave coupling for laser backscattering: Analytic solutions and kinetic simulations
论文作者
论文摘要
理解磁化激光 - 血浆相互作用对于控制磁惯性融合实验并开发磁性辅助辐射和粒子源很重要。在长脉冲方案中，相互作用由连贯的三波相互作用支配，其非线性耦合系数直到最近才在波浪与磁场以倾斜角度传播时才知道。在本文中，使用一个空间维度的粒子中的粒子模拟对暖流体理论预测的反向散射耦合系数进行了标准测试，并且当相互作用由电子介导的相互作用介导了电子介导的相互作用时，就可以在各种等离子体温度，磁场强度和激光繁殖角度上找到出色的协议。通过严格的协议使理论与模拟之间的系统比较成为可能：在理论方面，求解了线性化的三波方程的初始边界值问题，并且瞬时时间解决方案允许区分生长和阻尼的影响。在模拟侧，仔细选择参数并进行校准运行，以确保受刺激的运行得到良好的控制。将仿真数据拟合到分析解决方案会产生数值增长率，这些增长率与误差线中的理论预测相匹配。尽管发现温暖的流体理论在广泛的参数范围内有效，但也观察到了真正的动力学效应。
Understanding magnetized laser-plasma interactions is important for controlling magneto-inertial fusion experiments and developing magnetically assisted radiation and particle sources. In the long-pulse regime, interactions are dominated by coherent three-wave interactions, whose nonlinear coupling coefficients become known only recently when waves propagate at oblique angles with the magnetic field. In this paper, backscattering coupling coefficients predicted by warm-fluid theory is benchmarked using particle-in-cell simulations in one spatial dimension, and excellent agreements are found for a wide range of plasma temperatures, magnetic field strengths, and laser propagation angles, when the interactions are mediated by electron-dominant hybrid waves. Systematic comparisons between theory and simulations are made possible by a rigorous protocol: On the theory side, the initial boundary value problem of linearized three-wave equations is solved, and the transient-time solutions allow effects of growth and damping to be distinguished. On the simulation side, parameters are carefully chosen and calibration runs are performed to ensure that stimulated runs are well controlled. Fitting simulation data to analytical solutions yields numerical growth rates, which match theory predictions within error bars. Although warm-fluid theory is found to be valid for a wide parameter range, genuine kinetic effects have also been observed.
