Interplanetary scintillation observations of the high-latitude solar wind
Interplanetary scintillation observations of the high-latitude solar wind
复制标题
高纬度太阳风的行星际闪烁观测
DOI：
10.1007/bf00768782
复制
发表时间：
1995
影响因子：
10.3
通讯作者：
W. Coles
中科院分区：
文献类型：
--
作者：
W. Coles
在 ULYSSES 航天器到达太阳风的极地之前，唯一可用的高纬度测量是通过间接技术进行的。在 5R⊙ 和 200R⊙ 之间的太阳风区域中最富有成效的观测是射电散射技术系列，广义上称为行星际闪烁 (IPS)（Coles，1978）。使用各种无线电源可以获得有用的观测结果，例如航天器信标、行星雷达回波和紧凑宇宙源（类星体、活动星系核、脉冲星、星系微波激射器等）。然而，对于高纬度太阳风的测量，宇宙源提供了最广泛的覆盖范围，本次审查将仅限于此类观测。 IPS 观测在确定极地日冕洞（首次在软 X 射线发射中观察到）是快速太阳风流的来源方面发挥了非常重要的作用，这些快速太阳风流偶尔会延伸到赤道区域并被航天器观测到。在这里，我将回顾 IPS 技术，并显示上一个太阳周期内速度和湍流水平随纬度的变化。我还将概述最近的工作并讨论我们希望在 IPS 和 ULYSSES 观测之间进行的比较。
Until the ULYSSES spacecraft reached the polar regions of the solar wind, the only high-latitude measurements available were from indirect techniques. The most productive observations in regions of the solar wind between 5R⊙ and 200R⊙ have been the family of radio scattering techniques loosely referred to as Interplanetary Scintillation (IPS) (Coles, 1978). Useful observations can be obtained using a variety of radio sources, for example spacecraft beacons, planetary radar echoes and compact cosmic sources (quasars, active galactic nuclei, pulsars, galactic masers, etc.). However for measurement of the high-latitude solar wind cosmic sources provide the widest coverage and this review will be confined to such observations. IPS observations played a very important role in establishing that polar coronal holes (first observed in soft x-ray emission) were sources of fast solar wind streams which occasionally extend down to the equatorial region and are observed by spacecraft. Here I will review the IPS technique and show the variation of both the velocity and the turbulence level with latitude over the last solar cycle. I will also outline recent work and discuss comparisons that we hope to make between IPS and ULYSSES observations.