Numerical Simulations of Flare-productive Active Regions: δ-sunspots, Sheared Polarity Inversion Lines, Energy Storage, and Predictions
Numerical Simulations of Flare-productive Active Regions: δ-sunspots, Sheared Polarity Inversion Lines, Energy Storage, and Predictions
复制标题
DOI：
10.3847/1538-4357/aa95c2
复制
发表时间：
2017-11-20
影响因子：
4.9
通讯作者：
Takasao, Shinsuke
中科院分区：
文献类型：
--
作者：
Toriumi, Shin;Takasao, Shinsuke
众所周知，产生强烈耀斑和日冕物质抛射(CME)的太阳活动区(ARs)具有相对较高的非潜在性，并以三角洲太阳黑子和剪切磁结构为特征。在这项研究中，我们进行了从对流区到日冕的一系列通量涌现模拟，并模拟了四种类型的活动区，即点-点、点-卫星、四极和AR间的情况。因此，我们证实了三角斑的形成是由于浮现磁场的复杂几何形状和相互作用所致，并且我们发现强场、高梯度、高剪切的极性反转线(PIL)是由磁场的平流、伸展和压缩共同作用形成的。我们证明了自由磁能在PIL上方以电流片的形式积累起来。预测耀斑爆发的光球磁参数高精度地反映了耀斑爆发的存储自由能，而CME预测参数反映了耀斑带与整个区域之间的磁关系。
Solar active regions (ARs) that produce strong flares and coronal mass ejections (CMEs) are known to have a relatively high non-potentiality and are characterized by delta-sunspots and sheared magnetic structures. In this study, we conduct a series of flux emergence simulations from the convection zone to the corona and model four types of active regions that have been observationally suggested to cause strong flares, namely the spot-spot, spot-satellite, quadrupole, and inter-AR cases. As a result, we confirm that delta-spot formation is due to the complex geometry and interaction of emerging magnetic fields, and we find that the strong-field, high-gradient, highly sheared polarity inversion line (PIL) is created by the combined effect of the advection, stretching, and compression of magnetic fields. We show that free magnetic energy builds up in the form of a current sheet above the PIL. It is also revealed that photospheric magnetic parameters that predict flare eruptions reflect the stored free energy with high accuracy, while CME-predicting parameters indicate the magnetic relationship between flaring zones and entire ARs.