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G. H. Lin

Publications and source records attributed to G. H. Lin.

3 recordsLinked to original sources

Chinese Sunspot Drawings and Their Digitization-(VIII) Release of a Machine Readable Parameters Catalog

We present a systematically revised and manually verified digital catalog of historical sunspot drawing observations from Chinese observatories, encompassing sunspot number, sunspot group number, and sunspot area measurements. This represents an updated release of China's early sunspot drawings that have been utilized in numerous published studies over the years, with ongoing refinements and corrections progressively incorporated during the course of those studies and now consolidated through a systematic round of data revision aimed at improving internal consistency and usability for the broader research community. To facilitate scientific utilization, selected comparisons with international reference sunspot data are presented, focusing on relative sunspot numbers (RSN) and sunspot group numbers (GN) from Yunnan Observatory (YNO) and Purple Mountain Observatory (PMO), while sunspot area measurements are also included in this release but are not compared with international datasets in the present work. For RSN, both raw and k-corrected values are analyzed; for GN, only raw counts are used as no dedicated correction factor exists in the Chinese records. The results demonstrate strong positive correlations, with correlation coefficients consistently exceeding 0.95 for all comparisons, confirming the reliability and scientific value of these historical records. Systematic differences are observed: raw YNO RSN values are systematically higher than SIDC by about 17.6\%, while raw PMO RSN values are about 6.0\% lower. After k-correction, YNO shifts to a 20.9\% deficit, suggesting over-correction, while PMO remains lower with a 15.5\% deficit. Notably, GN exhibits smaller systematic offsets (16.5\% for YNO and 8.5\% for PMO) and serves as a more robust index for long-term solar cycle studies.

astro-ph.SR

Chinese Sunspot Drawing and Its Digitization-(I) Parameter Archives

Based on the Chinese historical sunspots drawings, a data set consisting of the scanned images and all their digitized parameters from 1925 to 2015 have been constructed. In this paper, we briefly describe the developmental history of sunspots drawings in China. This paper describes the preliminary processing processes that strat from the initial data (inputing to the scanning equipment) to the parameters extraction, and finally summarizes the general features of this dataset. It is the first systematic project in Chinese solar-physics community that the historical observation of sunspots drawings were digitized. Our data set fills in an almost ninety years historical gap, which span 60 degrees from east to west and 50 degrees from north to south and have no continuous and detailed digital sunspot observation information. As a complementary to other sunspots observation in the world, our dataset provided abundant information to the long term solar cycles solar activity research.

astro-ph.SR

Toward Standard Data Production for Magnetic Field Observations at Huairou Solar Observing Station

The productions of data with internationally agreed standards are the common pursuits for all astronomical observation instruments both ground and spacebased undoubtedly, Since standard data to facilitate the use of scientific research. The routine solar observations are available at Huairou Solar Observing Station (HSOS) since 1987, which should be regarded as one main solar observations in the world. The data storage medium and format at HSOS experienced several changes, so there exist some inconveniences for solar physicist. This paper shows that the observations data of HSOS are further processed both for storage medium and format toward international standards, in order to explore HSOS observations data for scientific research.

astro-ph.SR