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arXiv · 2006.09082

A New Comprehensive Data Set of Solar Filaments of 100 yr Interval. I

Abstract

Filaments are very common physical phenomena on the Sun and are often taken as important proxies of solar magnetic activities. The study of filaments has become a hot topic in the space weather research. For a more comprehensive understanding of filaments, especially for an understanding of solar activities of multiple solar cycles, it is necessary to perform a combined multifeature analysis by constructing a data set of multiple solar cycle data. To achieve this goal, we constructed a centennial data set that covers the H$\alpha$ data from five observatories around the world. During the data set construction, we encountered varieties of problems, such as data fusion, accurate determination of the solar edge, classifying data by quality, dynamic threshold, and so on, which arose mainly due to multiple sources and a large time span of data. But fortunately, these problems were well solved. The data set includes seven types of data products and eight types of feature parameters with which we can implement the functions of data searching and statistical analyses. It has the characteristics of better continuity and highly complementary to space observation data, especially in the wavelengths not covered by space observations, and covers many solar cycles (including more than 60 yr of high-cadence data). We expect that this new comprehensive data set as well as the tools will help researchers to significantly speed up their search for features or events of interest, for either statistical or case study purposes, and possibly help them get a better and more comprehensive understanding of solar filament mechanisms.

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GangHua Lin, GaoFei Zhu, Xiao Yang, YongLiang Song, Mei Zhang, Suo Liu, XiaoFan Wang, JiangTao Su, Sheng Zheng, JiaFeng Zhang, DongYi Tao, ShuGuang Zeng, HaiMin Wang, Chang Liu, Yan Xu. 2020-06-16. A New Comprehensive Data Set of Solar Filaments of 100 yr Interval. I. https://doi.org/10.3847/1538-4365/ab92a5

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