标题： 太阳风中由于波活动引起的表观温度各向异性 显示英文标题

标题： Apparent temperature anisotropies due to wave activity in the solar wind

摘要： 高速太阳风是一种碰撞稀疏的等离子体，其中充满了在许多不同尺度上的等离子体波。 等离子体波代表了电磁场周期性变化与相关等离子体粒子有序运动之间的自然相互作用。 在本文中，为处于单一、相干、大振幅波中的等离子体推导出一个模型速度分布函数。 该模型允许研究波运动对粒子分布的动能效应。 这些效应是通过在一定采样时间内统计来自不同方向且具有不同能量的粒子来测量的。 我们将结果与赫利俄斯探测器的测量结果进行比较，从而发现，通过假设高波活动，我们能够在我们的模型框架内解释测量分布的关键观测特征。 我们还讨论了最近关于非共振波-粒子相互作用和明显加热的争论。 所采用的时间平均过程会导致一种明显的离子温度各向异性，这种各向异性与底层分布函数的固有温度有关，但并不相同。 显示英文摘要

摘要： The fast solar wind is a collisionless plasma permeated by plasma waves on many different scales. A plasma wave represents the natural interplay between the periodic changes of the electromagnetic field and the associated coherent motions of the plasma particles. In this paper, a model velocity distribution function is derived for a plasma in a single, coherent, large-amplitude wave. This model allows one to study the kinetic effects of wave motions on particle distributions. They are by in-situ spacecraft measured by counting, over a certain sampling time, the particles coming from various directions and having different energies. We compare our results with the measurements by the Helios spacecraft, and thus find that by assuming high wave activity we are able to explain key observed features of the measured distributions within the framework of our model. We also address the recent discussions on nonresonant wave--particle interactions and apparent heating. The applied time-averaging procedure leads to an apparent ion temperature anisotropy which is connected but not identical to the intrinsic temperature of the underlying distribution function.