A macroscopic profile of the typical quasi-perpendicular bow shock - Isee 1 and 2
A macroscopic profile of the typical quasi-perpendicular bow shock - Isee 1 and 2
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典型准垂直弓激波的宏观轮廓 - Isee 1 和 2
DOI：
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发表时间：
1980
期刊：
影响因子：
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通讯作者：
H. Rème
中科院分区：
文献类型：
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作者：
E. W. Greensadt;C. Russell;J. Gosling;S. Bame;G. Paschmann;G. Parks;K. Anderson;F. Scarf;R. R. Anderson;D. A. Gurnet;R. Lin;C. Lin;H. Rème
1977 年 11 月 5 日记录的弓激波的场和粒子特性，通过比较 Isee 1 和 2 数据，早期被识别为稳定特征，并进行了宏观检查。描述了休克处于“典型”状态的程度，并结合多种诊断观察来定义休克轮廓，在这个已知的案例中，这让人想起从早期研究中收集的合成肖像。英尺、主波前梯度和后波前过冲表征了磁场。各种粒子测量揭示了相应的结构元素，包括双峰离子能量分布，其两个峰值大致位于太阳风流能量和流能量的 2 至 3 倍处。电子在主要的尖锐磁梯度之前被热化；离子在梯度上部分随机化，但离子热化过程直到梯度交叉后很长时间才完成。离子分布的第二个峰值代表主磁梯度上游的一组单独的反射粒子，它们在通过热化合并到一般分布之前在前沿后面相当大的距离内保持其特性。这个单独的组包括在前沿前面但不是紧随其后的向北质子通量。该集团最终通过一系列非常有规律的振荡而变得热化。正面太阳风整体速度的降低超过了根据与流动相反的电势上升的理想化一阶模型计算得出的总和，加上质子加热，使质子反射和波辐射和色散成为解释差异的候选者。离子声频率下的等离子体波活动在脚部和前面最强烈，并且似乎在反射粒子的外边界处增强。
Field and particle properties of the bow shock recorded on November 5, 1977, identified earlier as stable features by comparison of Isee 1 and 2 data, are examined macroscopically. The extent to which the shock was in a ‘typical’ state is described, and multidiagnostic observations are combined to define the shock profile, which, in this known case, is reminiscent of composite portraits assembled from earlier studies. A foot, a principal wave front gradient, and a postfront overshoot characterized the magnetic field. Various particle measurements revealed corresponding structural elements, including a bimodal ion energy distribution whose two peaks were at roughly the solar wind streaming energy and 2 to 3 times the streaming energy. The electrons were thermalized before the principal sharp magnetic gradient; the ions were partially randomized at the gradient, but the ion thermalization process was not completed until long after the gradient was crossed. The second peak of the ion distribution represented a separate group of reflected particles upstream of the main magnetic gradient that retained its identity for an appreciable distance behind the front before being merged by thermalization into the general distribution. This separate group included a northward proton flux in front of, but not immediately behind, the front. The group ultimately became thermalized through a series of very regular oscillations. The decrease in solar wind bulk velocity at the front exceeded the sum of that calculated from an idealized first-order model of the rise in potential opposing the flow, plus the proton heating, leaving proton reflection and wave radiation and dispersion as candidates to account for the discrepancy. Plasma wave activity, at ion acoustic frequencies, was most intense in the foot and at the front and appeared to be enhanced at the outer boundary of the reflected particles.