Plasma Jet Formation by Collision of Two Shock Waves and by Collision of Two Magnetic Flux Tubes

Abstract

We present numerical simulations of plasma jet formation by using a novel 2.5 dimension MHD code, employing the Artificial Wind concept which allows to construct simple upwind shock-capturing schemes. Firstly we investigate the formation process of a plasma jet by the collision of two shock waves propagating at some angle between the fronts and we compare our results with the theory. We found that there appear three cases for the jet formation: (1) Heat dominated, (2) Jet-Heat, and (3) Jet dominated case, depending on the parameters of the collision angle and the shock velocity. We also found that even in the case where the two flows behind the colliding shock fronts are both a sub-sonic, the super-sonic plasma jet still appears there. Next we investigate the generation process of super-sonic plasma jet during direct collision of two magnetic flux tubes. We found that super-sonic plasma jets appear in a wide range of parameters. From many parameter runs we concluded that there are three important physical...