The eruption of a prominence carrying coronal flux rope: forward synthesis of the magnetic field strength measurement by the COronal Solar Magnetism Observatory Large Coronagraph
From a magnetohydrodynamic (MHD) simulation of the eruption of a prominence hosting coronal flux rope, we carry out forward synthesis of the circular polarization signal (Stokes V signal) of the FeXIII emission line at 1074.7 nm produced by the MHD model as measured by the proposed COronal Solar Magnetism Observatory (COSMO) Large Coronagraph (LC) and infer the line-of-sight magnetic field BLOS above the limb. With an aperture of 150 cm, integration time of 12 min, and a resolution of 12 arcsec, the LC can measure a significant BLOS with sufficient signal to noise level, from the simulated flux rope viewed nearly along its axis with a peak axial field strength of about 10 G. The measured BLOS is found to relate well with the axial field strength of the flux rope for the height range of the prominence, and can discern the increase with height of the magnetic field strength in that height range that is a definitive signature of the concave upturning dipped field supporting the prominence. The measurement can also detect an outward moving BLOS due to the slow rise of the flux rope as it develops the kink instability, during the phase when its rise speed is still below about 41 km/s and up to a height of about 1.3 solar radii. These results suggest that the COSMO LC has great potential in providing quantitative information about the magnetic field structure of CME precursors (e.g. the prominence cavities) and their early evolution for the onset of eruption.
Many prominences are supported by magnetic flux ropes. One important question is how we can determine whether the flux rope is weakly-twisted or strongly-twisted. In this paper, we attempted to check whether prominences supported by weakly-twisted and strongly-twisted flux ropes can manifest different features so that we might distinguish the two types of magnetic structures by their appearance. We performed pseudo three-dimensional simulations of two magnetic flux ropes with different twists. We found that the resulting two prominences differ in many aspects. The prominence supported by a wea…
Prominence Formation Associated with an Emerging Helical Flux Rope
太阳磁共振的形成演化过程和磁结构至今仍不清楚。为了研究日珥的形成过程，我们利用\emph{Hinode}卫星上的太阳光学望远镜对NOAA AR 10953中的一个日珥进行了连续观测。正如我们在前一封信中所报道的，我们发现了一个信号，表明在一个预先存在的日珥下，一个螺旋形的通量绳从光球层下面出现。在这里，我们调查更详细的属性和光球迹象的新兴螺旋磁通绳，并讨论它们的关系，形成的日珥。我们的主要结论是：（1）在Ca \textsc{ii} H线滤波图中，没有强垂直磁场的暗区先变宽后变窄。这一现象与螺旋磁通绳作为光球对应物的出现是一致的。磁通绳的大小大约是30,000公里长，10,000公里宽。其宽度大于日珥的宽度。(2)没有剪切运动或收敛流的检测，但我们发现发散流，如沿极性反转线的中粒。中颗粒的存在可能与螺旋状磁通绳的出现有关。(3)出现的螺旋状磁通绳与之前存在的日珥的磁场重新连接，使日珥在接下来的几天里保持稳定。因此，我们推测日珥日冕磁场以螺旋磁通绳的形式出现，有助于日珥的形成和维持。
Aims. We begin by exploring the influence of two classes of commonly adopted heating models on the formation behaviour of solar prominences. These models consider either an exponential variation dependent on height alone, or local density and magnetic field conditions. We highlight and address some of the limitations inherent to these early approximations by proposing a new, dynamic 2D flux rope heating model that qualitatively accounts for the 3D topology of the twisted flux rope field. Methods. We performed 2.5D grid-adaptive numerical simulations of prominence formation via the levitation-c…
Numerical simulations of large-amplitude oscillations in flux-rope solar prominences
上下文太阳活动的大振幅振荡（LAO）是一种非常壮观但却知之甚少的现象。这些运动具有大于$10 {\mathrm{\, km \,s^{-1}}}$的幅度，并且可以由外部扰动触发，例如，摩顿波或EIT波。目标。我们的目的是分析使用现实的日珥模型的大振幅振荡的性质和触发机制的外部扰动。方法.我们使用具有剪切角和密度对比度两个值的磁通量绳模型对LAO进行了与时间相关的数值模拟。我们利用水平和垂直触发研究了日珥的内部模式。此外，我们使用来自外部的扰动，以了解这种外部干扰如何产生LAO。结果纵向振荡的周期及其随高度的变化与单摆模型吻合得很好。横向振荡的周期随高度保持不变，表明存在一个全局简正模。横向振荡通常具有比纵向振荡更短的周期。结论.纵、横振荡的周期与磁结构的剪切角和日珥密度差的关系很弱。外部扰动扰动的磁通绳激发振荡的两个极化。它们的性质是由纯水平和垂直驱动激发的性质的混合。
Quiescent solar prominences are observed to exist within the solar atmosphere for up to several solar rotations. Their eruption is commonly preceded by a slow increase in height that can last from hours to days. This increase in the prominence height is believed to be due to their host magnetic flux rope transitioning through a series of neighbouring quasi-equilibria before the main loss-of-equilibrium that drives the eruption. Recent work suggests that the removal of prominence mass from a stable, quiescent flux rope is one possible cause for this change in height. However, these conclusions …
Context. Prominence eruptions provide key observations to understand the launch of coronal mass ejections as their cold plasma traces a part of the unstable magnetic configuration. Aims. We select a well observed case to derive observational constraints for eruption models. Methods. We analyze the prominence eruption and loop expansion and contraction observed on 02 March 2015 associated with a GOES M3.7 class flare (SOL2015-03-02T15:27) using the data from Atmospheric Imaging Assembly (AIA) and the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). We study the prominence eruption…
We present magnetohydrodynamic (MHD) simulations of the evolution from quasi-equilibrium to eruption of a prominence-forming twisted coronal flux rope under a coronal streamer. We have compared the cases with and without the formation of prominence condensations, and the case where prominence condensations form but we artificially initiate the draining of the prominence. We find that the prominence weight has a significant effect on the stability of the flux rope, and can significantly increase the loss-of-equilibrium height. The flux rope can be made to erupt earlier by initiating draining of…
Multi-Viewpoint Observation of a Failed Prominence Eruption on the Sun
NASA Goddard Space Flight Center（美国国家航空航天局戈达德太空飞行中心）；Northumbria University（诺森比亚大学）；University of Graz（格拉茨大学）；New Jersey Institute of Technology（新泽西理工学院）；University of New Hampshire（新罕布什尔大学）
Large-scale solar eruptions are believed to have a magnetic flux rope as the core structure. However, it remains elusive as to how the flux rope builds up and what triggers its eruption. Recent observations found that a prominence erupted following multiple episodes of "flux feeding". During each episode, a chromospheric fibril rose and merged with the prominence lying above. In this letter, we carried out 2.5-dimensional magnetohydrodynamic (MHD) numerical simulations to investigate whether the flux-feeding mechanism can explain such an eruption. The simulations demonstrate that the discrete …
Prominences in the solar atmosphere represent an intriguing and delicate balance of forces and thermodynamics in an evolving magnetic topology. How this relatively cool material comes to reside at coronal heights, and what drives its evolution prior to, during, and after its appearance remains an area full of open questions. We deliberately focus on the levitation-condensation scenario, where a coronal flux rope forms and eventually demonstrates in-situ condensations, revisiting it at extreme resolutions down to order 6 km in scale. We perform grid-adaptive numerical simulations in a 2.5D tran…
The Spontaneous Genesis of Solar Prominence Structures Driven by Supergranulation in Three-Dimensional Simulations
School of Physics and Astronomy, Yunnan University（云南大学物理与天文学院）；Yunnan Key Laboratory of Solar Physics and Space Science（云南太阳能物理与空间科学重点实验室）；National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台）
We report a new, plasmoid-fed scenario for the formation of an eruptive prominence (PF$^2$), involving reconnection and condensation. We use grid-adaptive resistive two-and-a-half-dimensional magnetohydrodynamic (MHD) simulations in a chromosphere-to-corona setup to resolve this plasmoid-fed scenario. We study a pre-existing flux rope (FR) in the low corona that suddenly erupts due to catastrophe, which also drives a fast shock above the erupting FR. A current sheet (CS) forms underneath the erupting FR, with chromospheric matter squeezed into it. The plasmoid instability occurs and multiple m…
A rising cool column as signature for helical flux emergence and formation of prominence and coronal cavity
2006年12月23日至24日，利用太阳光学望远镜（SOT）对静止日珥进行了连续观测。在观测过程中，从低层大气中发展出一种特殊的缓慢上升的$/sim10^{4}$ K等离子体柱。柱的表观上升速度为2 km/s $^{-1}$，而柱的精细结构表现出更快的运动，高达20 km/s $^{-1}$。柱体最后变成一个微弱的低地突出物。与柱的出现相关联，在X射线和极紫外线中看到的覆盖冕腔在$/sim$ 5 km s $^{-1}$处向上移动。我们讨论了这些情节之间的关系，并建议，他们是由于出现了螺旋磁通绳，经历了与较低的日冕领域的重联，可能携带材料进入冠状腔。在出射通量假设下，柱体中2 km s $^{-1}$的低速和20 km s $^{-1}$的高速分别归因于出射通量的上升运动和出射通量与先存日冕场之间的磁重联驱动的外流。本文对螺旋绳上升柱的神秘现象及其对日冕的影响作了较好的解释。我们讨论的影响，出现这样的螺旋绳发电机过程中的对流区。
Large-scale contraction and subsequent disruption of coronal loops during various phases of the M6.2 flare associated with the confined flux rope eruption
Multi-wavelength synthesis of a flux rope-trapped mini-prominence eruption and post-flare coronal rain
Instituto de Astrofísica de Canarias（加那利天体物理研究所）；Universidad de La Laguna（拉古纳大学）；University of Helsinki（赫尔辛基大学）；Leibniz-Institut für Astrophysik Potsdam (AIP)（波茨坦莱布尼茨天体物理研究所）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；Northumbria University（诺森比亚大学）
Twisting/Swirling Motions During a Prominence Eruption as seen from SDO/AIA
利用太阳动力学天文台（SDO）上的大气成像组件（AIA）的不同通道观测了太阳西北侧的一个静止日珥。我们报告和分析扭曲/旋转运动期间和之后的突出爆发。我们将观察到的旋转运动分成小尺度和大尺度。小尺度的旋转运动表现在日珥的倒钩上，而大尺度的旋转则表现为日珥爆发时的横摇运动。我们注意到日珥的两个足点都是逆时针方向旋转的。我们认为，在两个足点相似的旋转感导致日珥爆发。日珥在南足点附近的爆发是不对称的，这可能是由于南足点附近的质量分布和空洞位置不均匀造成的。此外，我们还研究了日珥爆发后等离子体在日珥空腔中沿不同圆周路径的涡旋运动。沿不同圆周路径运动的等离子体的旋转速度估计为$\sim$ 9-40 km s $^{-1}$。这些涡旋运动可以用日珥空腔中扭曲的磁场线来解释。最后，我们观察到日珥中建立的扭曲，被日冕物质抛射（CME）带走，如在太阳和日光层天文台（SOHO）上的大角度光谱日冕物质抛射（LASCO）中所看到的。
A Major Geomagnetic Storm in 2024 October Linked to Sympathetic CME--Prominence Eruptions
State Key Laboratory of Solar Activity and Space Weather, National Space Science Center, Chinese Academy of Sciences（中国科学院国家空间科学中心太阳活动与空间天气重点实验室）；School of Astronomy and Space Sciences, University of Chinese Academy of Sciences（中国科学院大学天文与空间科学学院）；Key Laboratory of Space Weather, National Satellite Meteorological Center (National Center for Space Weather), China Meteorological Administration（中国气象局国家卫星气象中心（国家空间天气监测预警中心）空间天气重点实验室）；School of Microelectronics and Physics, Hunan University of Technology and Business（湖南工业大学微电子与物理学院）
Quiescent prominence dynamics observed with the Hinode Solar Optical Telescope . II. Prominence Bubble Boundary Layer Characteristics and the Onset of a Coupled Kelvin-Helmholtz Rayleigh-Taylor Instability
We investigate the transverse coronal-loop oscillations induced by the eruption of a prominence-carrying flux rope on 7 December 2012. The flux rope originating from NOAA Active Region (AR) 11621 was observed in EUV wavelengths by the SDO/AIA and in H$α$ line center by the ground-based telescope at the BBSO. The early evolution of the flux rope is divided into two steps: a slow rise phase at a speed of $\approx$230\,km\,s$^{-1}$ and a fast rise phase at a speed of $\approx$706\,km\,s$^{-1}$. The eruption generates a C5.8 flare and the onset of the fast rise is consistent with the HXR peak time…
