NO EVIDENCE FOR HEATING OF THE SOLAR WIND AT STRONG CURRENT SHEETS
NO EVIDENCE FOR HEATING OF THE SOLAR WIND AT STRONG CURRENT SHEETS
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DOI：
10.1088/2041-8205/739/2/l61
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发表时间：
2011-10
期刊：
影响因子：
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通讯作者：
J. Borovsky;M. Denton
中科院分区：
文献类型：
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作者：
J. Borovsky;M. Denton
强电流片是太阳风中质子加热的场所。在本研究中，强电流片定义为在128 s内太阳风磁场方向旋转>45°。在1998-2010年ACE太阳风数据集中，共分析了1 Au处的194，070个强电流片。在每个电流片的质子温度，质子比熵，和电子温度进行比较，在等离子体中的相同的量相邻的电流片。从统计学上讲，电流片处的等离子体并不比电流片外的等离子体更热或熵更高。这是作为证据，有没有显着的太阳风质子或电子在强电流片的局部加热。然而，电流片被发现在更热的太阳风等离子体中更普遍。这是因为在快速太阳风中比在慢速太阳风中计算出更多的电流片，并且快速太阳风比慢速太阳风更热。
It has been conjectured that strong current sheets are the sites of proton heating in the solar wind. For the present study, a strong current sheet is defined by a >45° rotation of the solar-wind magnetic-field direction in 128 s. A total of 194,070 strong current sheets at 1 AU are analyzed in the 1998–2010 ACE solar-wind data set. The proton temperature, proton specific entropy, and electron temperature at each current sheet are compared with the same quantities in the plasmas adjacent to the current sheet. Statistically, the plasma at the current sheets is not hotter or of higher entropy than the plasmas just outside the current sheets. This is taken as evidence that there is no significant localized heating of the solar-wind protons or electrons at strong current sheets. Current sheets are, however, found to be more prevalent in hotter solar-wind plasma. This is because more current sheets are counted in the fast solar wind than in the slow solar wind, and the fast solar wind is hotter than the slow solar wind.