恒星超级耀斑作为与太阳耀斑相似并且更加猛烈的爆发现象，对它们的相关研究在理解恒星内部结合与演化、恒星磁场活动性质和耀斑爆发机制等方面有着重要作用。另外，作为探索太阳系外行星宜居性和系外生命探测的重要影响因素，恒星超级耀斑多年来一直是天文学前沿研究的热点之一。在Kepler 和TESS 望远镜为我们传回大量的高精度测光数据后，我们得以对恒星上的这一剧烈的爆发现象拥有更为全面的认识。本文在恒星超级耀斑的筛选、能量计算、恒星黑子、耀斑参数与恒星参数的统计关系等方面综述了目前对恒星超级耀斑的探测手段以及研究成果。我们注意到，尽管在释放的能量上存在明显差异，但是恒星耀发和太阳耀斑在许多方面具有相似性：它们不仅具有相似的光变轮廓，且在能量的统计分布和耀斑时标方面也有诸多相似之处。虽然已经有了如此之多的证据表明太阳耀斑与恒星耀发存在类似的物理机制，但依然有很多与之相关的问题亟待解决。如：通过磁场重联理论对恒星耀斑持续时间的拟合结果并不是很理想；恒星耀斑的可见光连续谱辐射增强要明显大于太阳大型耀斑全日面可见光辐射的增强，并且有很长的持续时间；为什么缺乏对流层的恒星也会发生耀斑；恒星超级耀斑过程中X-射线辐射的占比要明显高于太阳耀斑中X 射线辐射的占比。理论与观测之间的差异，可能存在于一些目前手段难以探测到的地方，比如恒星耀斑的爆发结构。本文利用现有的耀斑爆发比例关系以及理论公式计算了EK Dra 一次耀斑爆发时的表面磁场，磁场大小范围在75-260 G 之间与目前推测的恒星表面磁场强度范围一致，这样的结果为我们理解恒星超级耀斑的爆发过程提供了全新的视角。最后对恒星超级耀斑统计结果和热点问题进行了总结。
其他摘要
Stellar superflares, as phenomena resembling solar flares but more intense in their eruption, play a crucial role in understanding the internal structure and evolution of stars, the nature of stellar magnetic field activity, and the mechanisms behind flare eruptions. Furthermore, as an important factor in exploring the habitability of exoplanets in the search for extrasolar life, stellar superflares have long been a focal point of cutting-edge astronomical research. With the vast amount of high-precision photometric data returned by the Kepler and TESS telescopes, we have gained a more comprehensive understanding of these intense eruption phenomena on stars. This thesis provides a comprehensive review of the current detection methods and research findings on stellar superflares, covering aspects such as the selection of superflares, energy calculations, starspots, and statistical relationships between flare parameters and stellar parameters. We note that despite significant differences in the released energy, stellar flares and solar flares share many similarities in various aspects: They not only exhibit similar light curve profiles but also share numerous similarities in the statistical distribution of energy and flare timescales. While there is a wealth of evidence suggesting similar physical mechanisms between solar flares and stellar flares, there are still many related questions that urgently need to be addressed. For instance, fitting the duration of stellar flares using magnetic reconnection theory results in less than ideal fits; the enhancement of visible continuum spectrum radiation during stellar flares is significantly greater than that of large solar flares across the entire solar disk, and it persists for much longer durations; why flares occur even in stars lacking a convective layer; and the proportion of X-ray radiation during stellar superflares is significantly higher than that observed during solar flares. The differences between theory and observation may stem from areas that are currently challenging to detect using available methods, such as the eruption structure of stellar flares. This thesis utilizes existing flare occurrence rate relationships and theoretical formulas to calculate the surface magnetic field of EK Dra during a single flare eruption, ranging from 75 to 260 G. This range aligns with the currently speculated intensity range of stellar surface magnetic fields, providing a fresh perspective for understanding the eruption processes of stellar superflares. Finally, this thesis summarizes the statistical results and hot topics regarding stellar superflares.
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