Abstract
We have compared a set of co-temporal magnetograms obtained with the Solar Magnetic Field Telescope (SMFT) of the Huairou Solar Observing Station (HSOS) and with the Spectro-Polarimeter of the Solar Optical Telescope (SP/SOT) on board Hinode to check the linear calibrations of SMFT vector magnetograms. The comparison shows that the currently used calibration coefficients of the SMFT have under-estimated the flux density and that a center-to-limb variation of the calibration coefficients was not taken into account by previous calibrations.
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Supported by the National Natural Science Foundation of China (Grant Nos. 40636031, 10778723, 10873038, and 10833007), the Important Directional Projects of Chinese Academy of Sciences (Grant No. KLCX2-YW-T04), and the National Basic Research Program of China (Grant No. 2006CB806301)
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Wang, D., Zhang, M., Li, H. et al. A comparison of co-temporal magnetograms obtained with the Huairou magnetograph and the Spectro-Polarimeter on board Hinode. Sci. China Ser. G-Phys. Mech. Astron. 52, 1707–1712 (2009). https://doi.org/10.1007/s11433-009-0249-0
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DOI: https://doi.org/10.1007/s11433-009-0249-0