Probabilistic models of the Jovian magnetopause and bow shock locations
Probabilistic models of the Jovian magnetopause and bow shock locations
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DOI：
10.1029/2001ja009146
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发表时间：
2002-10-01
影响因子：
2.8
通讯作者：
Ogino, T
中科院分区：
文献类型：
--
作者：
Joy, SP;Kivelson, MG;Ogino, T
通过将航天器观测与磁流体动力学(MHD)模拟得出的边界特征相结合，建立了木星磁层顶和弓形激波的新的三维模型。MHD模拟提供了太阳风动压参数的多项式形式。来自先驱者10号和11号、旅行者1号和旅行者2号、尤利西斯和伽利略的观测结果被用来确定木星周围区域落在这些边界表面之内或之外的可能性。磁层顶位置具有双峰概率分布，两个最可能的距离分别为63R-J(sigma=4R-J)和92R-J(sigma=6R-J)。弓形激波的位置分布呈双峰分布，但在95%的置信度水平下不能排除单一分布函数描述的可能性。平均弓激波对峙距离为84R-J(Sigma=16R-J)。对5.2AU(行星际磁场、动压和阿尔芬马赫数)附近的太阳风测量结果的分析表明，边界位置的双峰分布至少部分是由于木星附近太阳风参数的双峰分布。这些参数在太阳风扰动区域内和区域之间的概率密度分布在统计上是不同的，这是由相互作用区和日冕物质抛射引起的。在太阳周期内，这些参数的变化也较小。
New three-dimensional models of the Jovian magnetopause and bow shock were derived by combining spacecraft observations with boundary characteristics inferred from a magnetohydrodynamic (MHD) simulation. The MHD simulation provides polynomial forms parameterized by solar wind dynamic pressure. Observations from Pioneer 10 and 11, Voyager 1 and 2, Ulysses, and Galileo were used to establish the probability that regions surrounding Jupiter fall inside or outside these boundary surfaces. The magnetopause location was found to have a bimodal probability distribution with the two most probable standoff distances at 63 R-J (sigma=4 R-J) and 92 R-J (sigma=6 R-J). The bow shock location distribution appears bimodal, but a single distribution function description cannot be ruled out at the 95% confidence level. The mean bow shock standoff distance is 84 R-J (sigma=16 R-J). Analysis of solar wind measurements near 5.2 AU (interplanetary magnetic field, dynamic pressure, and Alfven Mach number) suggests that the bimodal distribution of boundary positions results at least in part from the bimodal distribution of solar wind parameters in the vicinity of Jupiter. The probability density distributions of these parameters within and between regions of disturbed solar wind, caused by corotating interaction regions and coronal mass ejections, are statistically distinct. Smaller variations were also observed in these parameters over the solar cycle.