Global configuration of Saturn's magnetic field derived from observations
Global configuration of Saturn's magnetic field derived from observations
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DOI：
10.1029/2010gl044622
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发表时间：
2010-11
影响因子：
5.2
通讯作者：
J. Carbary;N. Achilleos;C. Arridge;K. Khurana;M. Dougherty
中科院分区：
文献类型：
--
作者：
J. Carbary;N. Achilleos;C. Arridge;K. Khurana;M. Dougherty
卡西尼号航天器的磁场观测结果被平均到土星的 1 × 1 RS（1 RS = 60238 km）子午线箱中。龙格-库塔程序使用箱平均场分量来估计土星磁场的全局配置并绘制从赤道到土星电离层的场线。在土星 ∼18 RS 范围内，该映射很好地表示了土星磁场的子午形状，并证实了在 L ∼ 6 之外，磁场偏离偶极子并变成平滑扭曲的磁盘。圆盘在~15 RS的径向距离处向上翘曲多达~1 RS，并且翘曲随着径向距离而增加。当追溯到土星时，箱平均磁力线与电离层相交的纬度与根据最近的磁场模型预计的纬度相似；电离层皮尔斯纬度与简单偏置偶极子的预期相差多达 6°。
Magnetic field observations from the Cassini spacecraft are averaged into 1 × 1 RS (1 RS = 60238 km) meridional bins at Saturn. A Runge‐Kutta procedure uses the bin‐averaged field components to estimate the global configuration of Saturn's magnetic field and map field lines from the equator to Saturn's ionosphere. Within ∼18 RS of Saturn, the mapping gives a good representation of the meridional shape of Saturn's magnetic field and confirms that beyond L ∼ 6, the field departs from a dipole and becomes a smoothly‐warped magnetodisk. The disk warps upwards by as much as ∼1 RS at radial distances of ∼15 RS, with the warping increasing with radial distance. When traced back to Saturn, the bin average field lines intersect the ionosphere at latitudes similar to those expected on the basis of recent magnetic field models; the ionospheric pierce latitudes can differ by as much as 6° from those expected from a simple offset dipole.