太陽活動寧靜期日冕層影像與解析磁場模型之影像套疊與應用

The images fitting and applications between solar coronal images and an analytic solar magnetic field model

柳琮源(Tsung-yuan Liu)

指導教授 ： 葉永烜

國立中央大學/地球科學學院/太空科學研究所/碩士(2007年)

摘要

學習太陽物理的原因，除了要認識更多太陽和整個宇宙的形成知識以及現象外，還有瞭解太陽對地球的太空天氣產生影響的現象。我的論文中引用Banaszkiewicz等人在1998年發布的一個解析函數磁場模型，用此模型對SOHO衛星上的廣角日冕儀-LASCO拍攝的日冕層影像，兩者做影像的套疊。觀察影像中的日冕層冕流結構而選取合適的磁場結構，並且由磁場參數的大小來說明太陽表面的活動區域對冕流結構影響的程度。做了許多太陽活動寧靜期的影像與磁場的套疊後，整理出太陽表面的活動區域的確對日冕層的冕流結構產生影響，在太陽寧靜期時的LASCO影像中，可看到在赤道會有一條冕流的結構，但受到表面活動區域影響則會變為兩條。最後再討論使用此方法對冕流變化程度作量化時會遇到的問題。在未來的工作還可對冕流改變的程度與表面活動區域的種類做進一步的比較，以及研究各種由影像中預測太空天氣的方法。

關鍵字

磁場結構 ； 太陽影像 ； 日冕 ； 太陽

並列摘要

The reason why we study solar physics is not only to learn more about the sun and the entire universe, but also to study the effect of space weather on the earth. I introduce an analytic solar magnetic field model which was first proposed by Banaszkiewicz et al. in 1998. I use this model to fit the solar coronal images obtained by the LASCO instrument on the SOHO spacecraft. I examine the structures of the coronal streamers and choose a suitable magnetic field configuration. From an adjustment of the variable coefficient of the model, I can describe how the streamer structure may be caused by a sequence of the active region on the solar surface. After the performance of image processing and model fitting can routine through the solar minimum. I have found that the active regions indeed transform the coronal streamer form a linear shape into a two-lobe structure. And some possible applications are also described.

並列關鍵字

sun ； corona ； magnetic field structure ； solar image

參考文獻

Deforest C. E. et al., “OBSERVATION OF POLAR PLUMES AT HIGH SOLAR ALTITUDES”, ApJ, 546, 569D, 2001.

Dobrzycka D. et al., POLAR CORONAL JETS AT SOLAR MINIMUM”, ApJ, 565, 621D, 2002.

Neugebauer M. et al., “Spatial structure of the solar wind and comparisons with solar data and models”, JGR, 10314587N, 1998.

Neugebauer M. et al., “Sources of the solar wind at solar activity maximum”, JGRA, 107lSSH13N, 2002.

Liewer P. C. et al., “Determination of three-dimensional structure of coronal streamers and relationship to the solar magnetic field”, JGR, 10615903L, 2001.