太阳活动对地球及日地空间环境有着重大影响。太阳上存在着丰富多样的活动现象，如黑子，耀斑，日珥和日冕物质抛射。但这些只在太阳表面能用光学观测的方法看到其形态，由于不透明度的影响，我们不能直接观测到太阳内部。 在太阳表面的振荡现象被发现之后，以分析振动数据，探索太阳内部结构为目地的一个学科 迅速发展起来——日震学。日震学利用震波在太阳内部传递的特性，通过各种方法推测太阳内部的结构和流动等信息，得到了太阳内部极多的信息。 本文介绍作者在研究生期间的研究内容：太阳表面震波能量和磁场强度的关系，以及 西部太阳选址仪器日晕光度计的数据处理。包括： 1，过去的一系列研究表明在太阳光球表面,随着纵向磁场的增强，其震波能量降低。为了进一步研究震波和磁 场的关系，使用日震和磁成像仪(Helioseismic and Magnetic Imager，HMI) 的数据，通过对视向磁场进行势场外推得到磁场总强度，与震波能量进行关联。对一定总磁场区域的p模式震波能量拟合可以得到其随总磁场强度而变化的关系。研究证实了震波能量与磁场总强度有更强关联，不同活动区的结果表明p模式震波能量随着磁场总强度增加而下降的趋势在500高斯以下非常接近，在500高斯至1000高斯范围内有略微差别。并且p模式震波能量的自然对数与总磁场强度有较大的线性相关系数.对比迈克尔逊多普勒成像仪(Michelson Doppler Imager，MDI)和HMI得到的结果时发现，虽然MDI观测的磁场结果整体会比HMI观测结果偏大，但归一化p模式震波能量与磁场强度的关系分析对比结果相差不大。 2，现代日晕光度计是用于精确测定日间天文监测址点的多种大气参量的精密仪器，它已列为我国西部太阳设备选址工作当中的重要设备之一。在数据处理中日心坐标的选取对于处理结果有决定性影响，但由于观测过程中日面中心坐标会在图像上会随时间变化，因此我们发展了两种用于日面中心自动定位的方法：日面总强度法与傅立叶变换相关法。本文将仔细介绍这两种方法，并对比取得的结果差别。
其他摘要
The solar activities have a very huge impact to Sun-Earth space weather. Many kinds of active events exist on earth, such as sunspots, solar flares, prominences and coronal matter ejections. But all these phenomenon can only be seen by optic observation, and due to the Opacity of the solar inter structure, we can not see inside the sun. After the discovery of the solar surface oscillation, a subject called helioseismology based on data reduction of the oscillation data, and aim at detecting the inter structure of the sun has been founded.The oscillation of the sun travel through the sun, and observable on the solar surface, helioseismology can infer the solar inter structure and flow, gain information of the solar internal. This article mainly focus on the study of the author's research : relation of the solar surface acoustic power and magnetic field, the sky brightness monitor data reduction. 1，Series of research have shown that with the increase of magnetic field strength, the surface acoustic power decrease. We use the observed HMI LOS magnetic and potential field extrapolation method to calculate the total magnetic, and relate to the acoustic p-mode power. Use our fit method we could be able to get the relationship between the surface acoustic p-mode power and the total magnetic field strength. Our research finds that the acoustic p-mode power is related to the total magnetic field strength. Different active regions’ results have shown that the relationship of the normalized p-mode power and the total magnetic field strength is the same under 500G, is quite close at magnetic range 1000G-500G. Also the natural logarithm of the p-mode power and the total magnetic field strength has a very strong linear correlation coefficient. We compared the results between HMI and MDI instruments, find out the MDI magnetic measurement is much higher than HMI, and the comparison in p-mode power show little difference for HMI than MDI instruments. 2，The modern sky brightness monitor (SBM) is an exact tool used for precisely measuring various atmospheric parameters for daytime astronomical sites. It has been listed as an important instrument in our solar site survey program in west China. The instrument takes the multi-color photometric measurement and record the sky brightness varies in daytime in 4 wavelengths. The solar disk center measurement has a decisive affect for the sky brightness calculate from the original data. The solar disk center coordinate in the image varies with time because of the imperfectness observation conditions. With the greatly increased observe data, there is a strong needs to reduce those data automatically, so here we developed two automatic positioning methods to find the solar disk center coordinate: total intensity of solar disk and Fourier transform correlation method. The first method calculates the solar disk total intensity and find the maximum total disk intensity, locate as the solar disk and its center on the image; the second method uses the Fourier transform correlation between a mask of solar disk and the image changes the location of the mask and find the best correlation between the mask and the image. We also tested the solar disk coordinate get by these two methods, and find that the results are very close, indicate the two methods are consistent with each other and can alone find the solar disk center coordinate. With those two methods we will be able to reduce the SBM data and for future analyses.
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