磁光效应与太阳黑子磁场结构

本文在考虑磁光效应条件下,根据对斯托克斯参数转移方程组求得的数值解,计算了单极太阳黑子的线偏振讯号的单色像,并与美国马歇尔空间飞行中心的观测资料进行了对比,结果表明,径向黑子磁场模型给出与观测相似的单色像,而旋涡形模型导致与观测有显著差异的图像。因此可以认为径向模型更接近于实际情况。

The Magneto-Optical Effect and Structure of Sunspot Magnetic Fields

On the basis of a numerical solution of the equations of transfer of Stokes parameters under the action of the magmeto-optical effect we calculated monochromatic images of unipolar sunspots in the linear polarization signal U in this paper. Such images as secured with the vector magnetograph of Marshall Space Flight Center in the United States exhibit conspicuous spiral structures and this phenomenon once led M. J. Hag-yard et al. to believe that unipolar sunspots possess spiral magnetic fields. However, B. Landi DegPInnocenti has pointed out that under the action of the magneto-optical effect even radial magnetic fields can give rise to spiral U and Q monochromatic images. This interpretation agrees with our computations in 11. In this paper we have verified Landi Degl'Innocenti's conclusion with our numerical solution of Unno-Beckers' equations which is more accurate than his algebraic solution. Moreover, we have calculated U images not only with a radial fan-shaped model of spot magnetic fields but also with the spiral model established in 4]. By comparison of our results of computations with observations we may preliminarily conclude that the fan-shaped model is closer to reality than the spiral model of spot magnetic fields. We shall further study the structure of spot magnetic fields with quantitative U and Q monochromatic images.