One-Dimentional Numerical MHD Simulation of the Shock Events in the Outer Heliosphere

Abstract

Voyager 1 occasionally detected the sudden jumps of the interstellar magnetic field strength since its heliopause crossing in August，2012. These events are believed to be the interstellar shocks，and associated with the product of the interaction between the large-scale solar wind structures and the heliopause. In this paper, this possibility is examined by means of a two-fluid magnetohydrodynamics（MHD）simulation consisting of the solar wind plasma and the interstellar neutrals. Three different solar wind observations from OMNI，STEREO A and B at a heliocentric distance of 1 au during the year 2010－2017 are used as input to the simulation，and the evolution of solar wind in the outer heliosphere is investigated after the charge-exchange between solar wind and interstellar neutrals.The numerical results are compared with the observation from the two Voyagers，showing that the shock events in the interstellar medium observed by Voyager 1 have direct linkage with the pressure pulses in the inner heliosheath detected by Voyager 2.

Keywords

outer heliosphere / shock events / solar wind / numerical MHD simulation

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