The Sc II 4247 A line formed in the chromosphere is one of the lines well known, like the Na I D_2 and Ba II D_2, for its prominent triple peak structure in Q/I and the underlying quantum interference effects governing it. In this paper, we try to study the nature of this triple peak structure using the theory of F-state interference including the effects of partial frequency redistribution (PRD) and radiative transfer (RT). We compare our results with the observations taken in a quiet region near the solar limb. In spite of accounting for PRD and RT effects it has not been possible to reproduce the observed triple peak structure in Q/I. While the two wing PRD peaks (on either side of central peak) and the near wing continuum can be reproduced, the central peak is completely suppressed by the enhanced depolarization resulting from the hyperfine structure splitting. This suppression remains for all the tested widely different 1D model atmospheres or for any multi-component combinations of them. While multidimensional radiative transfer effects may improve the fit to the intensity profiles, they do not appear capable of explaining the enigmatic central Q/I peak. This leads us to suspect that some aspect of quantum physics is missing.
The role of quantum interference and partial redistribution in the solar Ba II D2 4554 A line
4554 A处的Ba II D2线是一个很好的例子,其中由于奇数同位素产生的F态干扰效应产生的偏振分布与那些没有表现出F态干扰的偶数同位素的偏振分布非常不同。因此,有必要考虑不同同位素的贡献,以了解这条线的观测线性偏振分布。在本文中,我们提出了辐射转移模型与部分频率重分布(PRD),这是必不可少的模拟这条线。这是因为完全频率再分布(CRD)不能再现所观察到的机翼极化。我们提出了观察和计算的Q/I的配置文件在不同的肢体距离。理论廓线强烈依赖于临边距离(μ),而在其它μ位置,拟合临边观测的模式大气则失效。
Modeling the quantum interference signatures of the Ba II D2 4554 A line in the second solar spectrum
量子干涉效应在形成太阳谱线的线性偏振轮廓中起着至关重要的作用。在4554 A处的Ba II D2线是一个突出的例子,其中由于奇数同位素产生的F态干扰效应产生的偏振分布与没有F态干扰的偶数同位素的偏振分布非常不同。因此,有必要考虑不同同位素的贡献,以了解这条线的观测线性偏振分布。在这里,我们做辐射转移建模与部分频率重新分布(PRD)的观测,同时占干扰效应和同位素组成。发现Ba II D2极化曲线强烈受PRD机制支配。我们展示了如何一个完整的PRD治疗成功地再现的意见,而完全的频率重新分配(CRD)单独未能产生偏振配置文件,有任何相似之处,与所观察到的。然而,我们也发现线中心偏振对模式大气的温度结构是敏感的。为了获得一个很好的拟合所观察到的斯托克斯Q/I分布的线中心峰,一个小的修改的WAX模型的大气是必要的,通过降低线形成层的温度。由于Ba II D2线的温度敏感性,它可能不是太阳色球层Hanle磁场诊断的合适工具,因为目前还没有直接的方法将温度和磁场效应相互分离。
Collisional effects on the formation of the second solar spectrum of the Sr {\sc ii} $λ$4078 line
这项工作的目的是提供关键要素,以获得更好地了解形成的第二太阳光谱的Sr II $λ$ 4078线。我们表明,在一定范围内的氢密度,Sr II离子与氢原子之间的各向同性碰撞的效果是重要的,在确定的极化的Sr II $λ$ 4078线。忽略Sr II的亚稳能级4d的原子模型的使用可以在太阳Sr II $λ$ 4078线的散射偏振值中引起高达25%的误差。
Polarized lines of the second solar spectrum (SrI, SrII, CaI, BaII) observed at the Pic du Midi Turret Dome spectropolarimeter with the slit orthogonal to the limb
Observatoire de Paris, PSL Research University(巴黎天文台,PSL研究大学)
利用 Pic du Midi 光谱偏振仪观测太阳边缘附近的第二太阳光谱,通过 Hanle 效应解释,精确测量了 SrI、SrII、CaI、BaII 等谱线的线性偏振率 Q/I,用于研究宁静太阳中的弱湍流未解析磁场。