Evidence suggests that a non-zero dawn–dusk interplanetary magnetic field (IMF $$B_y$$ ) can cause a rotation of the cross-tail current sheet/neutral sheet around its axis aligned with the Sun–Earth line in Earth’s magnetotail. We use Geotail, THEMIS and Cluster data to statistically investigate how the rotation of the neutral sheet depends on the sign and magnitude of IMF $$B_y$$ . In our dataset, we find that in the tail range of $$-30<$$ XGSM $$<-15$$ $$R_{\mathrm{E}}$$ , the degree of the neutral sheet rotation is clearly smaller, there appears no significant rotation or even, the rotation is clearly to an unexpected direction for negative IMF $$B_y$$ , compared to positive IMF $$B_y$$ . Comparison to a model by Tsyganenko et al. (2015, doi:10.5194/angeo-33-1-2015) suggests that this asymmetry in the neutral sheet rotation between positive and negative IMF $$B_y$$ conditions is too large to be explained only by the currently known factors. The possible cause of the asymmetry remains unclear.

中文翻译：

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是否由于IMF \（B_y \）符号导致地球磁尾中性片旋转不对称？

有证据表明，黎明至黄昏的行星际磁场（IMF $$ B_y $$）非零会导致交叉尾电流片/中性片绕其轴旋转，该轴与地球磁尾中的太阳-地球线对齐。我们使用Geotail，THEMIS和Cluster数据统计地调查中性表的旋转如何取决于IMF $$ B_y $$的符号和大小。在我们的数据集中，我们发现在$$-30 <$$ XGSM $$ <-15 $$ $$ R _ {\ mathrm {E}} $$的尾部范围内，中性图纸旋转的程度明显较小，则与否定的IMF $$ B_y $$相比，没有明显的轮换，甚至没有明显的转向。与Tsyganenko等人的模型进行比较。（2015，doi：10。5194 / angeo-33-1-2015）表明，正向和负向IMF $$ B_y $$条件之间的中性表旋转的这种不对称性太大，无法用目前已知的因素来解释。不对称的可能原因仍然不清楚。