Mechanics of Seismic Emission from Solar Flares
Mechanics of Seismic Emission from Solar Flares
复制标题
太阳耀斑地震发射的机制
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
A. Donea
中科院分区：
文献类型：
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作者：
C. Lindsey;A. Donea
在一些太阳耀斑的脉冲阶段发射到太阳内部的地震瞬变实例为理解太阳耀斑的物理学和当地日震学的一般发展提供了一个很有前途的诊断工具。已考虑的耀斑声发射的预期贡献者包括：1)由高能粒子对色球上部和中部的厚靶脉冲加热引起的压力瞬变引起的色球冲击；2)色球连续辐射或可能由高能质子引起的光球层加热；3)磁力瞬变引起的磁力瞬变。色球激波的流体动力学模型表明，辐射损失在色球穿透光球层之前，会耗尽最初沉积在色球中的能量的一小部分。从耀斑声发射表面特征的地震全息获得的声源的空间分布与可见光发射和磁特征突变的空间分布的比较，提供了一种区分光球加热和磁力瞬变对耀斑声发射的贡献的可能手段。在这项研究中，我们开发和测试了一种方法，用于估计与可见光发射相关的光球层加热产生的耀斑声发射的地震强度和空间分布，并将其与地震发射的日震特征进行比较。类似的技术也适用于瞬变磁特征。
Instances of seismic transients emitted into the solar interior in the impulsive phases of some solar flares offer a promising diagnostic tool, both for understanding the physics of solar flares and for the general development of local helioseismology. Among the prospective contributors to flare acoustic emission that have been considered are: i) chromospheric shocks propelled by pressure transients caused by impulsive thick-target heating of the upper and middle chromosphere by high-energy particles, ii) heating of the photosphere by continuum radiation from the chromosphere or possibly by high-energy protons, and iii) magnetic-force transients caused by magnetic reconnection. Hydrodynamic modeling of chromospheric shocks suggests that radiative losses deplete all but a small fraction of the energy initially deposited into them before they penetrate the photosphere. Comparisons between the spatial distribution of acoustic sources, derived from seismic holography of the surface signatures of flare acoustic emission, and the spatial distributions of sudden changes both in visible-light emission and in magnetic signatures offer a possible means of discriminating between contributions to flare acoustic emission from photospheric heating and magnetic-force transients. In this study we develop and test a means for estimating the seismic intensity and spatial distribution of flare acoustic emission from photospheric heating associated with visible-light emission and compare this with the helioseismic signatures of seismic emission. Similar techniques are applicable to transient magnetic signatures.