Research on the Effect of Opacity on Solar Coronal Soft X-ray OⅧ Spectral Line
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摘要: 为研究不透明度对日冕软X射线的影响,利用光子逃逸因子的基本理论,分析了不透明度对太阳日冕OⅧ光谱线强度比的影响,讨论了OⅧ 1.879nm光谱线的光学厚度,估算了太阳等离子体中OⅧ离子的辐射层有效厚度. 结果表明,不透明度对太阳 OⅧ光谱线有较大影响,其辐射层有效厚度比其他太阳紫外谱线大. 此研究对太阳等离子体发射层特性诊断具有重要参考意义.Abstract: To study the effect of opacity on solar plasma X-rays in solar coronal region, using the basic theory of photon escape factor in spectral analysis, the effect of opacity on intensity ratio of solar OⅧ 1.897nm and 1.601nm spectral lines is analyzed. Under optically thick conditions, theory of the effect of photon escape factor on the intensity ratio of the solar spectral lines is discussed. In the calculation, the optically depth of OⅧ spectral lines is discussed, and finally the effective emission thickness of OⅧ ion in solar plasma is estimated. Results show that under optically thick conditions, the opacity has great effect on solar OⅧ spectral line, and the effective emission thickness of OⅧ ion is greater than that in other solar ultraviolet spectral line. This is important for plasma diagnose in solar plasma emission layer.
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Key words:
- Escape factor /
- Opacity /
- OⅧ spectral lines /
- Optical depth
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