摘要
首先考察了谱线形成深度理论及其在诊断太阳大气中矢量磁场分层结构方面的应用，指出了分别与贡献函数和响应函数相关的方法的优缺点，然后用理论斯托克斯轮廓观察各轮廓参量沿视线方向梯度对轮廓尤其是它的对称性和极值点的影响，在此基础上提出了基本假设使偏振辐射转移方程在极值点得到极大的简化而创立了一种不依赖形成深度理论的新方法。它由四个操作构成，将其中三个操作作循环处理便可得到位于所考虑的沿深度方向格点化的层次上的各轮廓参量及表面以下不能观测到的斯托克斯轮廓。整个推导采用层层往下递推模式，导出的结果以矢量磁场尤其是场强大小最令人满意。作者分别用理论轮廓和实测轮廓作了拟合，结果发现拟合轮廓在所利用的谱线非远线翼部分与被拟合轮廓相符较好，能导出比较复杂的磁结构。但本方法也存在导出的深度范围不广及推导表面不能精确定位等问题。
Abstract In the thesis, the application of the line formation depth theory to diagnose the vector magnetic field stratification in solar atmosphere is examined. The advantages as well as disadvantages of the methods concerning the contribution function and response function are pointed out respectively. Then the influence of the gradients of the profile parameters on the profiles themselves, especially their symmetry as well as the extremum points are inrestigated. After this, the basic assumption is presented and it simplies greatly the polarized radiative transfer equations at the extremum points. Thus a new method is proposde, which is independent of the line formation depth theory, and consists of four operations. When three of the four operations are executed cyclically, the stratification of the profile parameters are obtained and the profiles under the surface are computed out. The diagnoses is operated down step by step, and the resulted parameters, especially the strength of the magnetic field ,are satisfactory. When fitting the synthetic and observed profiles, it is found that the fitting profiles and the fitted coincide well in the wavelength region where the method uses, and even the complicated structure of the magnetic fields can be extracted. But the method suffers from several problems, which include that the inferred depth region is narrow and the ‘surface’to which the inferred parameters are ascribed to can not be accurately determined.
出处
《云南天文台台刊》
CSCD
1998年第1期74-75,共2页
Publications of the Yunnan Observatoty
