模拟宁静太阳中涡旋驱动的磁通量绳的形成与爆发
Formation and Eruption of a Vortex-driven Magnetic Flux Rope in the Simulated Quiet Sun
- School of Astronomy and Space Science, Nanjing University（南京大学天文与空间科学学院）
- Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education（南京大学现代天文与天体物理教育部重点实验室）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究通过辐射MHD模拟，揭示了宁静太阳中涡旋驱动磁通量绳的形成与爆发过程，发现其爆发特征微弱但结构相似，有助于理解此类隐蔽事件。
AI中文摘要：
磁通量绳（MFR）是理解活动区耀斑和日冕物质抛射的关键结构，但它们在宁静太阳中的特征仍知之甚少。通过一个从上部对流区延伸到日冕的辐射磁流体动力学（MHD）模拟，我们分析了一个超米粒尺度的磁通量绳的形成与爆发。我们使用一种聚类方法，根据闭合磁力线的连通性对其进行分组。这些聚类进一步汇聚为8个持久的聚类集合（CAs），对应一个磁通量绳及其周围的磁结构。在超米粒汇聚点，即磁通量绳的正极足点处，维持着一个持久的逆时针涡旋。该涡旋持续将螺旋度注入磁通量管，并将周围的磁结构缠绕在中心磁通量管周围。在一小时的时间尺度上，该磁通量管演化为强扭转的磁通量绳并爆发。此次爆发表现出与活动区磁通量绳爆发推断出的电流片结构相似的特征；然而，其质量抛射和加热要弱得多，产生的可观测特征非常微弱。合成的极紫外（EUV）图像主要显示由膨胀磁通量绳中密度稀薄化引起的变暗特征。这项工作有助于阐明宁静太阳中形成的磁通量绳的动态且复杂的演化，并表明真实太阳中的类似事件可能因其隐蔽行为而被低估。
英文摘要：
Magnetic flux ropes (MFRs) are key structures for understanding flares and coronal mass ejections in active regions, but their characteristics in the quiet Sun remain poorly understood. With a radiative MHD simulation spanning from the upper convection zone to the corona, we analyze the formation and eruption of a supergranular-scale flux rope. We use a clustering method to group the closed field lines by their connectivity. The clusters are gathered further into 8 persistent cluster assemblies (CAs) that correspond to a flux rope and ambient magnetic structures. A persistent counterclockwise vortex is maintained at the converging point of the supergranules, i.e. the positive footpoint of the flux rope. The vortex continuously injects helicity into a magnetic flux tube and wraps ambient magnetic structures around the central flux tube. On a time scale of one hour, the flux tube evolves to a strongly twisted flux rope and erupts. The eruption exhibits similar current sheet structures as inferred from the flux rope eruption in active regions; however, the mass ejection and heating are much weaker and give rise to very insignificant observable features. The synthetic EUV images show mostly dimming features caused by density rarefaction in the expanding flux rope. This work helps elucidate the dynamic and complex evolution of flux ropes formed in the quiet Sun and suggests that similar events in the real Sun may have been underestimated due to their stealth behavior.
