Empirical models for the plasma convection at high latitudes from Millstone Hill observations
Empirical models for the plasma convection at high latitudes from Millstone Hill observations
复制标题
来自磨石山观测的高纬度等离子体对流的经验模型
DOI：
--
复制
发表时间：
1987
期刊：
影响因子：
--
通讯作者：
W. Oliver
中科院分区：
文献类型：
--
作者：
J. Holt;R. Wand;J. V. Evans;W. Oliver
1978年以来，在米尔斯通山(42.6°N，71.5°W)对55°<；Λ<；75°范围内的F区电场进行了雷达观测。从1978年1月至1981年8月期间进行的109个实验中收集的离子漂移数据计算了平均对流模式。大多数实验持续了24到48小时，超过3700,000个视线速度值被测定并包含在平均值中。观测到的速度被分类为磁当地时间间隔为半小时和顶点纬度间隔为2°的“箱”。在109个实验过程中，雷达在大范围的方位角上观察到了每个单元，从而确定了平均矢量速度。根据行星际磁场(IMF)是“朝向”太阳还是“远离”太阳，以及季节的不同，这些数据被进一步分为三个Kp级别。讨论了平均方向图，并与基于卫星和非相干散射数据的早期模型进行了比较。在所有季节和国际货币基金组织的取向下，Kp的模式都在扩大和加强。等离子体的极帽进出口点、细胞中心和极帽边界都取决于IMF。在个别日子可以清楚地看到的哈朗不连续，在平均水平上基本上消失了。
Since 1978, radar observations of F region electric fields within the region 55° < Λ < 75° have been made from Millstone Hill (42.6°N, 71.5°W). Averge convection patterns have been calculated from the ion drift data gathered in 109 of these experiments conducted between January 1978 and August 1981. Most of the experiments lasted between 24 and 48 hours, and over 3,700,000 values of the line-of-sight velocity were determined and included in the averages. The observed velocities were sorted into “bins” of ½-hour intervals of magnetic local time and 2° intervals of apex latitude. Each of these cells had been viewed by the radar over a wide range of aspect angles in the course of the 109 experiments, allowing the average vector velocity to be determined. The data were separated further into three levels of Kp, according to whether the interplanetary magnetic field (IMF) was “toward” or “away” from the sun, and by season. The average patterns are discussed and compared with earlier models based on satellite and incoherent scatter data. There is an expansion and intensification of the pattern with Kp for all seasons and IMF orientations. The polar cap entry and exit points of the plasma, the center of the cells, and the polar cap boundary all depend on the IMF. The Harang discontinuity, which can be seen clearly on individual days, is largely lost in the averages.