Interaction of a nonuniform solar wind with the local interstellar medium: 2. A two‐fluid model
Interaction of a nonuniform solar wind with the local interstellar medium: 2. A two‐fluid model
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非均匀太阳风与当地星际介质的相互作用：2.双流体模型
DOI：
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
G. Zank
中科院分区：
文献类型：
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作者：
H. Pauls;G. Zank
一个完整的三维模型的太阳风与当地星际介质的相互作用的结果。与星际中性氢的电荷交换的影响被考虑自洽，而热太阳风中性氢的影响，以及宇宙射线和磁场，在这项研究中被忽略。根据雅阁观测资料，假定太阳风与日纬度有关。两个大的，寿命长的极地日冕洞，一个在北方半球和另一个在南半球，被认为产生一个热的，低密度，高速风，边界一个冷却器，高密度，低速黄道风。太阳风边界条件允许太阳两极的太阳风冲压压力比黄道面增加1.5倍，该条件来自已发表的太阳能数据[菲利普斯等人，1995、1996年]。该模拟结果与Pauls和Zank [1996]描述的无电荷交换不对称太阳风模拟结果进行了比较。结果表明，由于冲压压力随日纬度的增加而增加，日球层沿着太阳两极的伸长，导致太阳两极的星际氢流入量大于黄道面的星际氢流入量。这反过来又减少了日光层沿着太阳两极的伸长程度。在无电荷交换模拟中发现的涡度，在存在电荷交换时不存在。Baranov和Malama [1993]和Pauls等人[1995]再次发现，太阳风与本地星际介质的相互作用受到电荷交换过程的强烈影响。
Results of a fully three-dimensional model of the interaction of the solar wind with the local interstellar medium are presented. The effects of charge-exchange with interstellar neutral hydrogen are taken into account self-consistently, while the effects of hot solar wind neutral hydrogen, as well as cosmic rays and magnetic fields, are ignored in this study. In accord with solar medium observations by Ulysses, the solar wind is assumed to depend on heliolatitude. Two large, long-lived polar coronal holes, one in the northern hemisphere and the other in the southern hemisphere, are assumed to produce a hot, low-density, high-speed wind which bounds a cooler, higher-density, low-speed ecliptic wind. The solar wind boundary conditions, which allow for a 1.5 increase in solar wind ram pressure over the poles of the Sun compared with the ecliptic plane, are drawn from published Ulysses data [Phillips et al., 1995, 1996]. The results of this simulation are compared with the no-charge-exchange asymmetric solar wind simulation, described by Pauls and Zank [1996]. It is found that the elongation of the heliosphere along the solar poles, resulting from the ram pressure increase with heliolatitude, induces a greater influx of interstellar hydrogen over the poles of the Sun than in the ecliptic plane. This, in turn, reduces the extent of elongation of the heliosphere along the poles of the Sun. The vorticity, found in the no-charge-exchange simulation, is absent in the presence of charge-exchange. Once again, as found by Baranov and Malama [1993] and Pauls et al. [1995], the interaction of the solar wind with the local interstellar medium is influenced strongly by charge-exchange processes.