Impact pressure shaping plasma jets and affected by high metallicity

High-Mach-number plasma jets have been extensively investigated in both astrophysical and laboratory contexts. In this work, we revisit the framework of magnetohydrodynamic (MHD) theory and introduce a new analytical approach for examining plasma jets generated by intense laser–plasma interactions. Specifically, we reformulate the fundamental MHD equations to elucidate the governing factors of local plasma density evolution. Furthermore, MHD simulations of laser irradiation on planar targets demonstrate that impact pressure plays a dominant role in the propagation of high-Mach-number plasma jets. In addition, a pronounced dependence on the atomic number is identified: higher-Z materials amplify the impact pressure, suggesting that metallicity exerts a significant influence on the morphology and dynamics of astrophysical jets.