A two‐dimensional, two‐component MHD model and the PPM scheme are used to investigate distribution of the density ratio (), magnetic field strength ratio (), gas pressure ratio (), and kinetic pressure jump() on the shock wave front at 1 AU in the inner helioshperic equatorial plane (the subscripts 1 and 2 represent the upstream and downstream sides respectively). Effects of the background solar wind velocity, the width and initial propagation direction of the disturbance source, and the presence of the interplanetary current sheet on the distribution are also studied. The main conclusions are as follows. (1) In an axial symmetric background, the stronger magnetic field region is situated at the western part of the shock wave front, whereas the kinetic pressure jump is larger at the eastern part. On the other hand, the density and gas pressure ratio are essentially symmetrical with respect to the normal across the source center. (2) The velocity of the background solar wind exerts a great influence on the kinetic pressure jump and the magnetic field ratio. The width of the disturbance source has no appreciable effect but the initial propagation direction of the disturbance has a significant effect on the distribution of the relevant parameters. (3) The presence of the current sheet directly affects the distribution of the parameters along the shock wave front. When the initial position of the current sheet does not coincide with the disturbance source, the peaks of the ratios of density, gas pressure and magnetic field strength deviate westward in longitude, whereas the peak of the kinetic pressure jump and the normal across the source center are located at the same side of the current sheet. When the center coincides with the current sheet, there exists a peak on each part of the shock wave front, i.e. a double peak structure, and moreover, the kinetic pressure jump is larger on the eastern part while the magnetic field strength is stronger on the western part.
Using a two‐dimensional, two‐component MHD model in the equatorial plane, this paper investigates the influence of the interplanetary electric current sheet on the distribution of the density ratio, the gas pressure ratio, the kinetic pressure jump, and the ratio of magnetic field strength along the shock front for shocks near 1 AU. It is shown that only with the disturbance source close to the current sheet can such influence be significant, and that this influence is stronger for shocks generated by disturbance sources on the eastern side of the current sheet. When the disturbance source is situated at the eastern (western) side of the current sheet, the peak of the kinetic parameters of the shock deviates eastward (westward) relative to the source central normal, and the westward deflection of the peak of the magnetic field strength ratio is weakened (strengthened). The influence of the current sheet is closely related to its effect on the deflection of the fastest propagation direction of the shock. On the other hand, the omnipresent westward deflection of the peak of the magnetic field strength ratio stems from the spiral structure of the interplanetary magnetic field.
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