Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 57522 10.12737/stp-92202301 Results of current research Results of current research Results of current research Latitudinal distribution of solar microflares and high-temperature plasma at solar minimum Latitudinal distribution of solar microflares and high-temperature plasma at solar minimum Кириченко Алексей Сергеевич Kirichenko Aleksey Sergeevich a.s.kiri4enko@gmail.com

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Лобода Иван Петрович Loboda Ivan Petrovich i.p.loboda@gmail.com Рева Антон Александрович Reva Anton Aleksandrovich reva.antoine@gmail.com Ульянов Артем Сергеевич Ulyanov Artyom Sergeevich ikiru@inbox.ru https://orcid.org/0000-0002-5448-8959 Богачев Сергей Александрович Bogachev Sergey Aleksandrovich bogachev.sergey@gmail.com

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 Институт космических исследований РАН Москва Россия Space Research Institute of RAS Moscow Russian Federation Институт космических исследований РАН Москва Россия Space Research Institute of RAS Moscow Russian Federation Институт космических исследований РАН Москва Россия Space Research Institute of RAS Moscow Russian Federation Институт космических исследований РАН Москва Россия Space Research Institute of RAS Moscow Russian Federation Институт космических исследований РАН Москва Россия Space Research Institute of RAS Moscow Russian Federation Самарский национальный исследовательский университет им. академика С.П. Королева Самара Россия Samara National Research University Samara Russian Federation 29 06 2023 29 06 2023 9 2 3 8 03 03 2023 18 04 2023 https://zh-szf.ru/en/nauka/article/57522/view

The paper analyzes the latitudinal distribution of high-temperature plasma (T>4 MK) and microflares on the solar disk during low solar activity in 2009. The distribution of A0.1–A1.0 microflares contains belts typical of ordinary flares of B class and higher. In total, we have registered 526 flares, most of which, about 96 %, occurred at high latitudes. About 4 % of microflares were found near the solar equator. We believe that they were formed by the residual magnetic field of previous solar cycle 23. Ordinary flares were almost not observed near the equator during this period. The number of microflares in the southern hemisphere was slightly higher than in the northern one. This differs from the distribution of ordinary flares for which the northern hemisphere was previously reported to be dominant.

The paper analyzes the latitudinal distribution of high-temperature plasma (T>4 MK) and microflares on the solar disk during low solar activity in 2009. The distribution of A0.1–A1.0 microflares contains belts typical of ordinary flares of B class and higher. In total, we have registered 526 flares, most of which, about 96 %, occurred at high latitudes. About 4 % of microflares were found near the solar equator. We believe that they were formed by the residual magnetic field of previous solar cycle 23. Ordinary flares were almost not observed near the equator during this period. The number of microflares in the southern hemisphere was slightly higher than in the northern one. This differs from the distribution of ordinary flares for which the northern hemisphere was previously reported to be dominant.

 microflares solar cycle plasma heating microflares solar cycle plasma heating The work was financially supported by the Russian Science Foundation (Grant No. 21-72-10157) The work was financially supported by the Russian Science Foundation (Grant No. 21-72-10157)

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