The solar XUV He I and He II emission lines. I - Intensities and gross center-to-limb behavior
The solar XUV He I and He II emission lines. I - Intensities and gross center-to-limb behavior
复制标题
太阳 XUV He I 和 He II 发射线。
DOI：
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发表时间：
1978
期刊：
影响因子：
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通讯作者：
J. Linsky
中科院分区：
文献类型：
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作者：
S. Mango;J. D. Bohlin;D. L. Glackin;J. Linsky
He II 304-和256-A线和He I 584-和537-A线的中心到边缘的变化是根据不同的太阳特征导出的，但在色球超颗粒结构上是平均的。总的趋势是在宁静的太阳区域临边增亮，在单极磁区（UMR）临边中性，在极冕洞临边变暗。在这些光学厚发射线的中心到肢体的行为表明碰撞激发和减少过渡区的温度梯度相对于光学深度在序列安静的太阳UMR日冕洞。
The center-to-limb variation of the He II 304- and 256-A lines and He I 584- and 537-A lines is derived for different solar features, but averaged over the chromospheric supergranulation structure. The general trend is for limb brightening in quiet-sun regions, limb neutrality in unipolar magnetic regions (UMR), and limb darkening in polar coronal holes. The center-to-limb behavior in these optically thick emission lines indicates collisional excitation and decreasing transition-region temperature gradients with respect to optical depth in the sequence quiet sun to UMR to coronal hole.