标题： 2024年5月多个日冕物质抛射的磁相互作用分析导致历史性的地磁风暴 显示英文标题

标题： Magnetic interaction analysis of multiple interplanetary coronal mass ejections leading to a historic geomagnetic storm in May 2024

摘要： 星际日冕物质抛射（ICMEs），这种能够释放大量太阳磁螺旋和能量的大尺度爆发现象，有可能引发强烈的地磁风暴。 它们在其他大尺度结构例如ICMEs之前和之后复杂地演化。 多个ICMEs之间的磁相互作用可能导致强烈且持续时间长的地磁风暴。 我们的目标是通过研究它们的磁含量，例如螺旋度、能量以及多个ICMEs之间的磁相互作用，来理解一个复杂太阳风结构的两个中尺度分离对应物之间地球效应显著变化的原因。 我们利用了2024年5月10-11日过去二十年最强地磁风暴期间，Wind和太阳地球关系观测台-A（STA）航天器的太阳风原位观测数据以及STA上的日球成像仪。 我们的研究证实了五个ICMEs之间的复杂相互作用导致了一个合并的大尺度结构内的不同对应物。 这些对应物具有显著不同的磁含量。 我们得出结论，由STA观测到的具有共同起源的ICMEs之间相互作用形成的复杂对应物，有利于磁重联，其总磁能和螺旋度分别比包含由Wind观测到的左手性丝状体起源ICME的对应物高1.6倍和2.8倍。 左手性ICME与周围右手性、共同起源的ICMEs不利于磁重联。 因此，尽管这两个中等分离的对应物属于同一个太阳风结构，但它们可能引发不同的地球效应。 这最终挑战了基于早期观测的空间天气预测。 显示英文摘要

摘要： Interplanetary coronal mass ejections (ICMEs), the large-scale eruptive phenomena capable of shedding a huge amount of solar magnetic helicity and energy are potential in driving strong geomagnetic storms. They complexly evolve while preceded and followed by other large-scale structures e.g. ICMEs. Magnetic interaction among multiple ICMEs may result intense and long-lived geomagnetic storms. Our aim is to understand the reason of substantial changes in the geoeffectivity of two meso-scale separated counterparts of a complex solar wind structure through investigating their magnetic content e.g. helicity, energy and magnetic interaction among multiple ICMEs. We utilized the insitu observations of solar wind from Wind and Solar Terrestrial Relations Observatory-A (STA) spacecraft during the strongest geomagnetic storm period in past two decades on May 10-11, 2024 and heliospheric imagers onboard STA. Our investigation confirms complex interactions among five ICMEs resulting in distinct counterparts within a coalescing large-scale structure. These counterparts possess substantially different magnetic contents. We conclude that the complex counterpart resulted from the interaction among common-origin ICMEs observed by STA, favorably orientated for magnetic reconnection, had 1.6 and 2.8 times higher total magnetic energy and helicity, respectively, than the counterpart containing a left-handed filament-origin ICME observed by Wind. The left-handed ICME non-favorably oriented for magnetic reconnection with the surrounding right-handed, common-origin ICMEs. Therefore, two medium-separated counterparts despite belonging to a common solar wind structure, were potential to lead different geoeffectivity. This ultimately challenges space weather predictions based on early observations.