Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 103581 10.12737/stp-113202503 20TH ANNUAL CONFERENCE “PLASMA PHYSICS IN THE SOLAR SYSTEM”. FEBRUARY 10–14, 2025, SPACE RESEARCH INSTITUTE RAS, MOSCOW, RUSSIA 20TH ANNUAL CONFERENCE “PLASMA PHYSICS IN THE SOLAR SYSTEM”. FEBRUARY 10–14, 2025, SPACE RESEARCH INSTITUTE RAS, MOSCOW, RUSSIA 20TH ANNUAL CONFERENCE “PLASMA PHYSICS IN THE SOLAR SYSTEM”. FEBRUARY 10–14, 2025, SPACE RESEARCH INSTITUTE RAS, MOSCOW, RUSSIA Effect of solar activity and solar wind parameters on plasma temperature and density in Earth’s plasmasphere Effect of solar activity and solar wind parameters on plasma temperature and density in Earth’s plasmasphere https://orcid.org/0000-0002-8488-8654 Котова Галина Аврамовна Kotova Galina Avramovna kotova@iki.rssi.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 https://orcid.org/0000-0002-5809-0921 Чугунин Дмитрий Владимирович Chugunin Dmitriy Vladimirovich dimokch@mail.ru Безруких Владилен Владимирович Bezrukikh Vladilen Vladimirovich bezrukikh31@mail.ru Институт космических исследований РАН Москва Россия Space Research Institute 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 22 09 2025 22 09 2025 11 3 22 30 10 03 2025 03 04 2025 https://zh-szf.ru/en/nauka/article/103581/view

Measurements from the Interball-1 and Magion-5 satellites of the Interball mission in 1995–2001 have been used to analyze the dependence of the equatorial plasmasphere characteristics on magnetic local time, as well as on solar activity, dynamic pressure, and solar wind density. The proton density at solar minimum is on average higher than at solar maximum, which is probably due to changes in plasma mass composition in the plasmasphere at solar maximum. The daytime and nighttime proton temperatures increase with increasing solar extreme ultraviolet flux, at least in the years of solar maximum. The plasmaspheric plasma density and thermal pressure rise with increasing dynamic pressure and/or density of the undisturbed solar wind, which might be associated with restructuring of the convective electric field in the magnetosphere.

Measurements from the Interball-1 and Magion-5 satellites of the Interball mission in 1995–2001 have been used to analyze the dependence of the equatorial plasmasphere characteristics on magnetic local time, as well as on solar activity, dynamic pressure, and solar wind density. The proton density at solar minimum is on average higher than at solar maximum, which is probably due to changes in plasma mass composition in the plasmasphere at solar maximum. The daytime and nighttime proton temperatures increase with increasing solar extreme ultraviolet flux, at least in the years of solar maximum. The plasmaspheric plasma density and thermal pressure rise with increasing dynamic pressure and/or density of the undisturbed solar wind, which might be associated with restructuring of the convective electric field in the magnetosphere.

 cold plasma density temperature magnetic local time solar activity geomagnetic activity solar wind pressure cold plasma density temperature magnetic local time solar activity geomagnetic activity solar wind pressure

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