AI 中文总结
该研究发现日冕环解旋产生的反向磁扭转转移会在光球形成黑子痕迹，为日冕物质抛射等相关光球变化提供定量解释，警示黑子磁场意外演化。
AI 中文摘要
稀薄太阳日冕中的磁场演化主要受下方稠密光球的运动支配。然而，相互作用的日冕磁场间的磁重联驱动的日冕磁场重构有时会反向作用于改变光球磁场，但该反应机制仍未确定。本文报告一种反向反应现象的发现：喷发期间重联时扭转的日冕环的解旋，会在其远离喷发的足点边界处产生增强的电流，表现为黑子痕迹的增长。借助联合空间观测和磁流体动力学模拟，揭示该现象源于磁扭转从日冕到低层大气的阿尔文反向转移。这些发现为与日冕物质抛射和/或耀斑相关的多数令人困惑的光球变化提供了可行且定量的解释，并警示黑子和星斑中存在意外的磁场演化。
英文摘要
The evolution of magnetic fields in the tenuous solar corona is predominantly governed by the motions of the underlying dense photosphere. Despite, coronal magnetic restructuring driven by magnetic reconnection between interacting coronal fields can sometimes react backwards to change photospheric magnetic fields. However, the mechanism of reactions remains undetermined. Here, we report the discovery of a back-reaction phenomenon: the untwisting of coronal loops that become twisted during reconnection in an eruption results in enhanced currents at the boundary of their footpoint away from the eruption, manifesting as the growth of a sunspot scar. It is revealed to arise from the Alfvenic reverse transfer of magnetic twist from the corona to the lower atmosphere, thanks to joint space observations and a magnetohydrodynamics simulation. These findings provide a viable and quantitative interpretation for the majority of puzzling photospheric changes associated with coronal mass ejections and/or flares and warn for unexpected magnetic field evolutions in sunspots and starspots.
Comments37 pages, 9 figures; published in Science Advances
