The Solar Wind and Heliospheric Current System in the Years of Maximum and Minimum Solar Activity
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Within the axisymmetric MHD model of the solar wind, the magnetic field of the Sun has been analyzed in two phases of the solar cycle: the minimum activity, when the dipole magnetic field dominates and the maximum activity, when the quadrupole field predominates. It has been shown that during the period of maximum solar activity, the heliospheric current sheet acquires a conical shape and shifts to high latitudes up to 30° above the ecliptic plane. In the opposite hemisphere, at the same latitudes, a second current sheet of conical shape with an azimuth current of the opposite direction is established. It has been shown that the profiles of the main characteristics of the solar wind become steeper with distance from the Sun, and their amplitudes decrease, in this case, for the quadrupole field, the dependences of the main characteristics of the solar wind are more complex. A comparison of the results of the model with averaged characteristics of the solar wind shows a good match between the observed values and model parameters.
We are grateful to Academician L.M. Zeleny, Director of the Space Research Institute, Russian Academy of Sciences for valuable remarks and attention to this study. E.V. Maiewski and A.A. Petrukovich acknowledge the support of Program no. 28 of the Presidium of the Russian Academy of Sciences. Kh.V. Malova acknowledges the support of the Russian Foundation for Basic Research (project no. 16-02-00479 and 16-52-16009). R.A. Kislov acknowledges the support of the Russian Foundation for Basic Research (project no. 17-02-01328). V.Yu. Popov acknowledges the support of the state program Plasma. O.V. Khabarova acknowledges the support of the International Space Science Institute (ISSI) within the framework of the work of International Team 405 Current Sheets, Turbulence, Structures, and Particle Acceleration in the Heliosphere, and the Russian Foundation for Basic Research (project nos. 16-02-00479 and 17-02-00300).
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