Interpretation of vector magnetograph data including magneto-optic effects
Interpretation of vector magnetograph data including magneto-optic effects
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DOI：
10.1007/bf00196176
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发表时间：
1983-10
期刊：
影响因子：
2.8
通讯作者：
E. West;M. Hagyard
中科院分区：
文献类型：
--
作者：
E. West;M. Hagyard
本文研究了在黑子横向磁场方位测量中存在的法拉第旋转。利用马歇尔航天飞行中心（MSFC）的矢量磁像仪获得的观测结果，推导出一个简单的，对称的太阳黑子的矢量磁场被用来计算程度的法拉第旋转的方位角的横向磁场作为波长的函数从斯托克斯参数的解析表达式。然后将这些结果与观测到的磁场方位角的旋转进行比较，磁场方位角的旋转是从Fei 5250 λ谱线内不同波长的观测中得出的。结果表明：当谱线形成参数ηois在黑子上变化时，理论公式能较好地模拟观测到的方位角旋转，谱线强度数据证实了η ois的变化，对于MSFC系统，当场强小于1800 G，场倾角大于45°时，法拉第旋转可以忽略;为了使太阳黑子本影中的法拉第旋转效应最小化，必须在塞曼敏感谱线的远翼进行MSFC磁象仪测量。
In this paper, the presence of Faraday rotation in measurements of the orientation of a sunspot's transverse magnetic field is investigated. Using observations obtained with the Marshall Space Flight Center's (MSFC) vector magnetograph, the derived vector magnetic field of a simple, symmetric sunspot is used to calculate the degree of Faraday rotation in the azimuth of the transverse field as a function of wavelength from analytical expressions for the Stokes parameters. These results are then compared with the observed rotation of the field's azimuth which is derived from observations at different wavelengths within the Fei5250 Å spectral line. From these comparisons, we find: the observed rotation of the azimuth is simulated to a reasonable degree by the theoretical formulations if the line-formation parameterηois varied over the sunspot; these variations inηoare substantiated by the line-intensity data; for the MSFC system, Faraday rotation can be neglected for field strengths less than 1800 G and field inclinations greater than 45°; to minimize the effects of Faraday rotation in sunspot umbrae, MSFC magnetograph measurements must be made in the far wings of the Zeeman-sensitive spectral line.