EFFECT OF LARGE-SCALE INHOMOGENEITY OF SOLAR WIND VELOCITY ON DISTRIBUTION OF DIRECTIONS OF INTERPLANETARY MAGNETIC FIELD VECTOR
Journal Title: Solar-Terrestrial Physics - Year 2019, Vol 5, Issue 3
Abstract
Using data with hourly resolution obtained in near-Earth heliosphere in 1965–2014, we have calculated statistical characteristics of the angles describing the direction of the interplanetary magnetic field (IMF): root-mean-square deviations of azimuthal and elevation angles, asymmetries of their distributions, and coefficient of correlation of the angles. It has been shown that the above characteristics varied in the course of solar cycle, and some of them changed their signs when solar polar magnetic field reversed. The results obtained from the experimental data analysis were compared with a model describing transport of large-scale disturbances of IMF lines by the inhomogeneous solar wind. The comparison has shown that the variations in the angular distribution of IMF in the course of solar cycle probably occur due to the appearance of the large-scale latitudinal gradient of solar wind velocity during solar minima. In addition, the angular distribution of IMF has been found to be substantially affected by the longitudinal velocity gradient in trailing parts of high-speed streams and short-term local-scale variations in velocity gradients.
Authors and Affiliations
Erofeev D. V.
Keywords
Related Articles
- EP ID EP702084
- DOI 10.12737/stp-53201905
- Views 106
- Downloads 0
GEOMAGNETIC VARIATIONS IN THE FREQUENCY RANGE 2.5–12 HZ IN THE IONOSPHERIC F LAYER AS MEASURED BY SWARM SATELLITES
We have analyzed geomagnetic variations in the 2.5–12 Hz frequency range in the ionospheric F layer above the electron density maximum, using data from two SWARM satellites. The analysis is based on the data obtained und...
NUMERICAL ANALYSIS OF THE SPATIAL STRUCTURE OF ALFVÉN WAVES IN A FINITE PRESSURE PLASMA IN A DIPOLE MAGNETOSPHERE
We have carried out a numerical analysis of the spatial structure of Alfvén waves in a finite pressure inhomogeneous plasma in a dipole model of the magnetosphere. We have considered three magnetosphere models differing...
Heating manifestations at the onset of the 29 June 2012 flare
Analysis of GOES data for the SOL2012-06-29T04:09 flare, class C4.6, shows a thermal character of the energy release for several minutes before the impulsive stage. Plasma heating to temperatures above 10 MK leads to the...
ANALYTICAL MODEL OF THE PLANETARY BOW SHOCK FOR VARIOUS MAGNETIC FIELD DIRECTIONS BASED ON MHD CALCULATIONS
Study of physical processes in plasma near planets often requires knowledge of the position and shape of the planetary bow shock. Empirical models are usually used since theoretical MHD and kinetic models consume too muc...
INFLUENCE OF THE ß SOLAR WIND PARAMETER ON STATISTICAL CHARACTERISTICS OF THE AP INDEX IN THE SOLAR ACTIVITY CYCLE
We have studied the effect of the β solar wind parameter (equal to the ratio of the plasma pressure to the magnetic pressure) on statistical characteristics of the Ap index reflecting the triggering behavior of the activ...