Toward Improved Understanding of Magnetic Fields Participating in Solar Flares: Statistical Analysis of Magnetic Fields within Flare Ribbons
Toward Improved Understanding of Magnetic Fields Participating in Solar Flares: Statistical Analysis of Magnetic Fields within Flare Ribbons
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DOI：
10.3847/1538-4357/ac3af3
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发表时间：
2021-11
期刊：
影响因子：
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通讯作者：
M. Kazachenko;B. Lynch;A. Savcheva;Xudong Sun;B. Welsch
中科院分区：
文献类型：
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作者：
M. Kazachenko;B. Lynch;A. Savcheva;Xudong Sun;B. Welsch
强烈的太阳耀斑和日冕物质抛射（cme）是磁现象。然而，由于缺乏对耀斑磁场性质的研究，耀斑中重联的磁场与非耀斑磁场有何不同仍不清楚。在这里，我们提出了第一个统计研究的耀斑（突出的耀斑带）矢量磁场在光球。我们的系统方法使我们能够描述太阳耀斑磁性的关键物理特性，包括磁通量、磁切变、垂直电流和活跃区域（AR）上耀斑与非耀斑部分的净电流的分布，并将这些与耀斑/CME特性进行比较。我们的分析表明，耀斑是由与AR大小成比例的物理性质引导的，比如参与重联过程的总磁通量和总电流（广泛性质），cme是由平均性质引导的，比如参与重联过程的AR磁通量的比例（密集性质），很少依赖于极性反转线（PIL）处的剪切量或净电流。我们发现，非中和电流与PIL处的剪切量成正比，这提供了直接证据，表明净垂直电流是由任何可能沿PIL产生磁剪切的机制形成的。我们还发现喷发事件往往比受限事件具有较小的PIL通量和较大的磁切变。我们的分析为更真实的太阳和恒星耀斑模型提供了参考。该数据库可在线获取，并可用于未来耀斑磁性的定量研究。
Violent solar flares and coronal mass ejections (CMEs) are magnetic phenomena. However, how magnetic fields reconnecting in the flare differ from nonflaring magnetic fields remains unclear owing to the lack of studies of the flare magnetic properties. Here we present a first statistical study of flaring (highlighted by flare ribbons) vector magnetic fields in the photosphere. Our systematic approach allows us to describe the key physical properties of solar flare magnetism, including distributions of magnetic flux, magnetic shear, vertical current, and net current over flaring versus nonflaring parts of the active region (AR), and compare these with flare/CME properties. Our analysis suggests that while flares are guided by the physical properties that scale with AR size, like the total amount of magnetic flux that participates in the reconnection process and the total current (extensive properties), CMEs are guided by mean properties, like the fraction of the AR magnetic flux that participates (intensive property), with little dependence on the amount of shear at the polarity inversion line (PIL) or the net current. We find that the nonneutralized current is proportional to the amount of shear at the PIL, providing direct evidence that net vertical currents are formed as a result of any mechanism that could generate magnetic shear along the PIL. We also find that eruptive events tend to have smaller PIL fluxes and larger magnetic shears than confined events. Our analysis provides a reference for more realistic solar and stellar flare models. The database is available online and can be used for future quantitative studies of flare magnetism.