Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 36813 10.12737/stp-61202002 Results of current research Results of current research Results of current research Investigating the influence of geometry of the heliospheric neutral current sheet and solar activity on modulation of galactic cosmic rays with a method of main components Investigating the influence of geometry of the heliospheric neutral current sheet and solar activity on modulation of galactic cosmic rays with a method of main components https://orcid.org/0000-0003-2184-8089 Гололобов Петр Юрьевич Gololobov Peter Yur'evich gpeter@ikfia.sbras.ru Кривошапкин Прокопий Антипович Krivoshapkin Prokopy Antipovich p_a_krivoshapkin@mail.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Крымский Гермоген Филиппович Krymsky Germogen Filippovich krymsky@ikfia.ysn.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 https://orcid.org/0000-0003-1247-4513 Герасимова Сардаана Кимовна Gerasimova Sardaana Kimovna danagsk@mail.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Институт космофизических исследований и аэрономии им. Ю.Г. Шафера СО РАН Якутск Россия Yu.G. Shafer Institute of Cosmophysical Research and Aeronomy SB RAS Yakutsk Russian Federation Институт космофизических исследований и аэрономии им. Ю.Г. Шафера СО РАН Якутск Россия Yu.G. Shafer Institute of Cosmophysical Research and Aeronomy SB RAS Yakutsk Russian Federation Институт космофизических исследований и аэрономии им. Ю.Г. Шафера СО РАН Якутск Россия Yu.G. Shafer Institute of Cosmophysical Research and Aeronomy SB RAS Yakutsk Russian Federation Институт космофизических исследований и аэрономии им. Ю.Г. Шафера СО РАН Якутск Россия Yu.G. Shafer Institute of Cosmophysical Research and Aeronomy SB RAS Yakutsk Russian Federation 6 1 24 28 https://zh-szf.ru/en/nauka/article/36813/view

The work studies the cumulative modulating effect of the geometry of the interplanetary magnetic field's neutral current sheet and solar activity on propagation of galactic cosmic rays in the heliosphere. The role of each factor on the modulation of cosmic rays is estimated using a method of main components. The application of the method to experimental data on solar activity, to the tilt angle of the neutral sheet, and cosmic ray intensity for a long period from 1980 to 2018 allows us to reveal the temporal dynamics of roles of these factors in the modulation. The modulation character is shown to strongly depend on the polarity of the Sun’s general magnetic field. Results of the study confirm the existing theoretical concepts of the heliospheric modulation of cosmic rays and reflect its peculiarities for almost four full cycles of solar activity.

The work studies the cumulative modulating effect of the geometry of the interplanetary magnetic field's neutral current sheet and solar activity on propagation of galactic cosmic rays in the heliosphere. The role of each factor on the modulation of cosmic rays is estimated using a method of main components. The application of the method to experimental data on solar activity, to the tilt angle of the neutral sheet, and cosmic ray intensity for a long period from 1980 to 2018 allows us to reveal the temporal dynamics of roles of these factors in the modulation. The modulation character is shown to strongly depend on the polarity of the Sun’s general magnetic field. Results of the study confirm the existing theoretical concepts of the heliospheric modulation of cosmic rays and reflect its peculiarities for almost four full cycles of solar activity.

 cosmic ray modulation interplanetary magnetic field neutral current sheet solar activity cosmic ray modulation interplanetary magnetic field neutral current sheet solar activity

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