High-Speed Jets in Earth’s Magnetosheath Downstream of the Quasi-Parallel Shock: A Two-Dimensional Global Hybrid Simulation

<p><span>High-speed jets (HSJs) occur frequently in Earth&#8217;s magnetosheath downstream of the quasi-parallel bow shock. They have great impacts on the magnetosheath and the magnetosphere. Using a two-dimensional global hybrid simulation, we investigate the formation and evolution of the HSJs with an IMF cone angle of 0&#176;</span><span>. The quasi-parallel shock is near the subsolar point, and t</span><span>he HSJs begin to appear in the quasi-parallel magnetosheath with a parallel (perpendicular) scale size of about 1R_E</span><span> (0.2R_E</span><span>). These HSJs then converge, leading to the formation of a large-scale HSJ with a parallel (perpendicular) scale size of</span> <span>6R_E</span><span> (1.2R_E</span><span>). </span><span>Some long HSJs, with a large parallel but small perpendicular scale size, are formed at the quasi-parallel bow shock and extend toward the quasi-perpendicular magnetosheath along with the background magnetosheath flow. Moreover, these long HSJs can cause filamentary structures in the magnetosheath.</span></p>