论文标题
在前两个帕克太阳能探测器中的小型磁通绳
Small-scale Magnetic Flux Ropes in the First two Parker Solar Probe Encounters
论文作者
论文摘要
小规模的磁通绳（SFR）是具有螺旋磁场线的太阳风中的一种结构。在最近的一份报告（Chen＆Hu 2020）中，我们使用Helios，Ace/Ace/Wind，Ulysses和Voyager Spacecraft的原位测量值介绍了SFR从0.29到8 AU的径向变化。随着Parker太阳能探针（PSP）的推出，我们将先前的研究进一步扩展到内部的Heliosphere。我们应用基于毕业生的基于SHAFRANOV的算法在前两个PSP遇到期间识别SFR。我们发现，在太阳附近检测到的SFR数量远小于较大的径向距离，在较大的径向距离上，磁流失动力学（MHD）的湍流可能是生产这些结构的局部来源。 Alfgenic结构的患病率显着抑制了SFR在近距离的检测。我们将SFR事件列表与其他事件识别方法进行比较，得出十几个匹配的事件。两个选定事件的横截面图证实了圆柱磁通量绳构型。 SFR磁场和HeliePentric距离之间的强力关系似乎降至0.16 au。
Small-scale magnetic flux ropes (SFRs) are a type of structures in the solar wind that possess helical magnetic field lines. In a recent report (Chen & Hu 2020), we presented the radial variations of the properties of SFR from 0.29 to 8 au using in situ measurements from the Helios, ACE/Wind, Ulysses, and Voyager spacecraft. With the launch of the Parker Solar Probe (PSP), we extend our previous investigation further into the inner heliosphere. We apply a Grad-Shafranov-based algorithm to identify SFRs during the first two PSP encounters. We find that the number of SFRs detected near the Sun is much less than that at larger radial distances, where magnetohydrodynamic (MHD) turbulence may act as the local source to produce these structures. The prevalence of Alfvenic structures significantly suppresses the detection of SFRs at closer distances. We compare the SFR event list with other event identification methods, yielding a dozen well-matched events. The cross-section maps of two selected events confirm the cylindrical magnetic flux rope configuration. The power-law relation between the SFR magnetic field and heliocentric distances seems to hold down to 0.16 au.
