Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 82731 10.12737/stp-103202409 19TH ANNUAL CONFERENCE “PLASMA PHYSICS IN THE SOLAR SYSTEM”. FEBRUARY 5–9, 2024, SPACE RESEARCH INSTITUTE RAS, MOSCOW, RUSSIA 19TH ANNUAL CONFERENCE “PLASMA PHYSICS IN THE SOLAR SYSTEM”. FEBRUARY 5–9, 2024, SPACE RESEARCH INSTITUTE RAS, MOSCOW, RUSSIA 19TH ANNUAL CONFERENCE “PLASMA PHYSICS IN THE SOLAR SYSTEM”. FEBRUARY 5–9, 2024, SPACE RESEARCH INSTITUTE RAS, MOSCOW, RUSSIA Conditions for the occurrence of intense fluxes of energetic electrons at L<1.2 associated with solar activity and solar wind parameters Conditions for the occurrence of intense fluxes of energetic electrons at L<1.2 associated with solar activity and solar wind parameters Суворова Алла Васильевна Suvorova Alla Vasil'evna all@yahoo.com

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Дмитриев Алексей Владимирович Dmitriev Alexei Vladimirovich dalex@jupiter.ss.ncu.edu.tw Научно-исследовательский нститут ядерной физики им. Д.В. Скобельцина МГУ Москва Россия Skobeltsyn Institute of Nuclear Physics, Moscow State University Moscow Russian Federation Научно-исследовательский институт ядерной физики им. Д.В. Скобельцина МГУ, Москва , Россия Москва Россия Skobeltsyn Institute of Nuclear Physics, Moscow State University, Moscow , Russian Federation Moscow Russian Federation Факультет космических наук и инженерии, Национальный Центральный Университет, Тайвань Тайвань Китайская Республика Department of Space Science and Engineering, National Central University, Taiwan Taiwan Taiwan 29 09 2024 29 09 2024 10 3 75 82 30 04 2024 17 06 2024 https://naukaru.ru/en/nauka/article/82731/view

We present the results of a statistical study of transient enhancements of electrons with energies >30 keV at low drift shells in the quasi-trapped region (forbidden zone) at the geomagnetic equator. Using data from low-altitude NOAA/POES and MetOp satellites, we have compiled a catalog of events with forbidden energetic electron (FEE) enhancements for the period from 1998 to 2023. Statistical analysis of FEE events has revealed solar-cyclic, as well as seasonal and diurnal variations in the occurrence of FEE enhancements. We have examined the correlation of the annual frequency of FEE events with solar activity, solar wind parameters, and geomagnetic activity. Strong correlations have been found with the F10.7 index of solar activity (radio emission flux) as well as with the Alfvén Mach number (solar wind parameter). An interpretation of the obtained results is proposed which is based on the mechanism of electrical drift and radial transport of electrons from Earth’s inner radiation belt to the quasi-trapped region (L<1.2). The key factor for the operation of the mechanism is the effective penetration of the electric field to low latitudes when a significant difference in the conductivity of the high-latitude ionosphere occurs in the illuminated and unilluminated sectors of local time under conditions of weakening auroral activity.

We present the results of a statistical study of transient enhancements of electrons with energies >30 keV at low drift shells in the quasi-trapped region (forbidden zone) at the geomagnetic equator. Using data from low-altitude NOAA/POES and MetOp satellites, we have compiled a catalog of events with forbidden energetic electron (FEE) enhancements for the period from 1998 to 2023. Statistical analysis of FEE events has revealed solar-cyclic, as well as seasonal and diurnal variations in the occurrence of FEE enhancements. We have examined the correlation of the annual frequency of FEE events with solar activity, solar wind parameters, and geomagnetic activity. Strong correlations have been found with the F10.7 index of solar activity (radio emission flux) as well as with the Alfvén Mach number (solar wind parameter). An interpretation of the obtained results is proposed which is based on the mechanism of electrical drift and radial transport of electrons from Earth’s inner radiation belt to the quasi-trapped region (L<1.2). The key factor for the operation of the mechanism is the effective penetration of the electric field to low latitudes when a significant difference in the conductivity of the high-latitude ionosphere occurs in the illuminated and unilluminated sectors of local time under conditions of weakening auroral activity.

 inner radiation belt quasi-trapped electrons solar-terrestrial relationships inner radiation belt quasi-trapped electrons solar-terrestrial relationships The work was carried out under the research theme “Solar research, monitoring, and modeling of the radiation environment and plasma processes in the heliosphere and geospace” The work was carried out under the research theme “Solar research, monitoring, and modeling of the radiation environment and plasma processes in the heliosphere and geospace”

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