论文标题
测量有效的太阳风质子的有效无均值路径
A Measurement of the Effective Mean-Free-Path of Solar Wind Protons
论文作者
论文摘要
弱碰撞等离子体受到非线性弛豫过程的约束，该过程的速度比粒子碰撞频率快得多。这会导致血浆像磁化流体一样反应，尽管没有颗粒的均值无均值路径。在这封信中，有效的碰撞机制在血浆动力学方程式中进行建模，以产生密度，压力和磁场响应，以与1 au处太阳风压缩波动的航天器测量值进行比较。这可以测量太阳风质子的有效无均值路径，发现为4.35 $ \ times 10^5 $ km，这是$ \ sim 10^3 $乘坐的均值均值均值均值。这些测量结果显示出在质子吉拉迪乌斯上方的尺度上支持太阳风的有效流体行为，并证明有效的碰撞过程会改变弱碰撞等离子体的热力学和运输。
Weakly collisional plasmas are subject to nonlinear relaxation processes, which can operate at rates much faster than the particle collision frequencies. This causes the plasma to respond like a magnetised fluid despite having long particle mean-free-paths. In this Letter the effective collisional mechanisms are modelled in the plasma kinetic equation to produce density, pressure and magnetic field responses to compare with spacecraft measurements of the solar wind compressive fluctuations at 1 AU. This enables a measurement of the effective mean-free-path of the solar wind protons, found to be 4.35 $\times 10^5$ km, which is $\sim 10^3$ times shorter than the collisional mean-free-path. These measurements are shown to support the effective fluid behavior of the solar wind at scales above the proton gyroradius and demonstrate that effective collision processes alter the thermodynamics and transport of weakly collisional plasmas.
