Two Practical Methods for Coronal Intensity Determination
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Determining the relative brightness of the solar corona is one of the most critical stages in solar eclipse studies. For this purpose, images taken with different exposures and polarization angles in white-light observations are used. The composite image of each polarization angle is produced by combining the images of different exposures. With the help of the intensity calibration function of these images, the relative intensity of the corona can be calculated. The total brightness of the solar corona is calculated using Stokes parameters obtained from intensity values of three polarization angles. In this study, two methods are presented: the first is used to obtain the intensity calibration function of the photographic material using calibration images, and the second is used to calculate the combined intensity values of images taken with different polarization angles.
KeywordsEclipse observations Corona, active Brightness, polarization
Thanks to Başar Coşkunoğlu for his contributions for improving the language of the manuscript. Thanks especially to M. Türker Özkan and Adnan Ökten and all other staff in charge of the observations of the 1999 and 2006 solar eclipses. Thanks also to the anonymous referee for their valuable suggestions and comments that improved the manuscript. This work was supported by the Istanbul University Scientific Research Projects Commission with the project numbers 24242, UP-16/160399, and 470/27122005.
Disclosure of Potential Conflicts of Interest
The author declares that he has no conflicts of interest.
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