Relativistic modeling capabilities in perseus extended MHD simulation code for HED plasmas

Summary form only given. We have developed a relativistic version of the PERSEUS extended MHD simulation code for HED plasmas, and validated our code for several test problems. Nonrelativistic PERSEUS solves the two-fluid equations, formulated in terms of a generalized Ohm´s law (GOL), so as to model about nine orders of magnitude in density variation using a local semi-implicit method. Relativistic PERSEUS preserves this structure and therefore retains these advantageous properties, enabling it to model relativistic HED phenomena with computational domains spanning a broad range of dynamical scales. These include laser-plasma interactions, hybrid X-pinches, and power feed loss through electrode surface plasmas. We have also overcome a major technical challenge associated with solving a relativistic system of equations relating conserved quantities (momentum, energy, etc.) to primitive variables (density, velocity, and pressure). Relativistic PERSEUS recovers expected nonrelativistic results, and uncovers new physics in relativistic simulations.