arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1207.0692astro-ph.SR
收藏

宁静太阳中的普适线偏振信号

Pervasive Linear Polarization Signals in the Quiet Sun

L. R. Bellot Rubio, D. Orozco Suárez

摘要:

本文利用超深偏振光谱数据研究了宁静太阳网络中线偏振信号的分布。我们减少噪音的意见,尽可能多的是可行的,通过增加单缝测量塞曼敏感的Fe I 630 nm线所采取的日出分光偏振仪。积分斯托克斯光谱用于确定由线偏振信号覆盖的视场的分数。我们发现,在盘中心,高达69%的安静太阳表面显示出振幅大于0.032%的斯托克斯Q或U轮廓(是较长积分所达到的7 x 10^{-5}噪声水平的4.5倍)。在大多数安静的太阳中,仅仅存在线性偏振就意味着弱的网络间场必须高度倾斜,但是我们通过将这些像素与斯托克斯Q或U信号反转来量化这一点。这允许场倾斜、场强度和场方位角的精确确定,因为同时使用所有四个斯托克斯光谱所携带的信息。在1.3 x 10^{-4}的噪声水平下,对53%的观测视场进行反演。因此,导出的磁场分布代表了安静的太阳互联网的一半以上。我们的研究结果证实了从以前的分析中得出的结论,主要使用斯托克斯I和V:互联网络领域是非常倾斜的,但除了在方位角,他们似乎不是各向同性分布。

英文摘要:

This paper investigates the distribution of linear polarization signals in the quiet Sun internetwork using ultra-deep spectropolarimetric data. We reduce the noise of the observations as much as is feasible by adding single-slit measurements of the Zeeman-sensitive Fe I 630 nm lines taken by the Hinode spectropolarimeter. The integrated Stokes spectra are employed to determine the fraction of the field of view covered by linear polarization signals. We find that up to 69% of the quiet solar surface at disk center shows Stokes Q or U profiles with amplitudes larger than 0.032% (4.5 times the noise level of 7 x 10^{-5} reached by the longer integrations). The mere presence of linear polarization in most of the quiet Sun implies that the weak internetwork fields must be highly inclined, but we quantify this by inverting those pixels with Stokes Q or U signals well above the noise. This allows for a precise determination of the field inclination, field strength, and field azimuth because the information carried by all four Stokes spectra is used simultaneously. The inversion is performed for 53% of the observed field of view at a noise level of 1.3 x 10^{-4}. The derived magnetic distributions are thus representative of more than half of the quiet Sun internetwork. Our results confirm the conclusions drawn from previous analyses using mainly Stokes I and V: internetwork fields are very inclined, but except in azimuth they do not seem to be isotropically distributed.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑