Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 22241 10.12737/stp-42201801 Results of current research Results of current research Results of current research The presence of a systematic error in SDO/HMI data The presence of a systematic error in SDO/HMI data Руденко Георгий Владимирович Rudenko Georgiy Vladimirovich rud@iszf.irk.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 Дмитриенко Ирина Сергеевна Dmitrienko Irina Sergeevna dmitrien@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation 4 2 3 7 https://zh-szf.ru/en/nauka/article/22241/view

In this paper, we came to the conclusion that there is a systematic error in SDO/HMI (Helioseismic and Magnetic Imager aboard the Solar Dynamics Observatory) vector magnetic data, which reveals itself in a deviation from the radial direction of the knot magnetic fields manifesting themselves on magnetograms in the form of small grains in a strong magnetic field. This deviation demonstrates a dependence on the distance to the disk center, which cannot be a property of the magnetic field – it can only be artificially introduced into the data. We suggest a simple method for correcting vector magnetograms, which eliminates the detected systematic error.

In this paper, we came to the conclusion that there is a systematic error in SDO/HMI (Helioseismic and Magnetic Imager aboard the Solar Dynamics Observatory) vector magnetic data, which reveals itself in a deviation from the radial direction of the knot magnetic fields manifesting themselves on magnetograms in the form of small grains in a strong magnetic field. This deviation demonstrates a dependence on the distance to the disk center, which cannot be a property of the magnetic field – it can only be artificially introduced into the data. We suggest a simple method for correcting vector magnetograms, which eliminates the detected systematic error.

 Sun magnetic field vector magnetograms Sun magnetic field vector magnetograms

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