Determining the LIC H density from the solar wind slowdown
Determining the LIC H density from the solar wind slowdown
复制标题
根据太阳风减速确定 LIC H 密度
DOI：
10.1051/0004-6361:20078565
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发表时间：
2008
影响因子：
6.5
通讯作者：
D. McComas
中科院分区：
文献类型：
--
作者：
J. Richardson;Y. Liu;Chi Wang;D. McComas
上下文电离的太阳风直接与流入日光层的星际中性粒子相互作用。这些中性粒子被电离，主要是通过电荷交换，然后加速到太阳风的速度，动量和能量从太阳风的整体流动中移除。因此，通过测量太阳风的减速，人们可以估计星际中性密度。目标。在2005年7月，位于5 Au的太阳和接近80 Au的旅行者2号处于同一日纬度。我们使用这种对齐来确定这两个航天器之间的太阳风速度下降。方法.的数据被用来作为输入的1-D MHD模型，其中包括拾取离子的影响。我们删除了一段被ICME污染的数据，该ICME指向旅行者2号。结果旅行者2号的速度与模型结果的比较显示，在彗星和旅行者2号之间，太阳风的速度降低了67 km s −1，与星际中性密度在0.09 cm −3的终止激波相一致。
Context. The ionized solar wind interacts directly with the interstellar neutrals which flow into the heliosphere. These neutrals are ionized, mainly by charge exchange, then accelerated to the solar wind speed with the momentum and energy removed from the bulk flow of the solar wind. Thus, by measuring the solar wind slowdown, one can estimate the interstellar neutral density. Aims. In July 2005, Ulysses at 5 AU and Voyager 2 near 80 AU were at the same heliolatitude. We use this alignment to determine the solar wind speed decrease between these two spacecraft. Methods. Ulysses data are used as input to a 1-D MHD model which includes the effects of pickup ions. We removed a section of data contaminated by an ICME directed toward Voyager 2. Results. Comparison of the Voyager 2 speeds with the model results shows that the solar wind speed decreased by 67 km s −1 between Ulysses and Voyager 2, consistent with an interstellar neutral density at the termination shock of 0.09 cm −3 .