A Simulation Study of Ultra-relativistic Jets. II. Structures and Dynamics of FR-II Jets

We study the structures of ultra-relativistic jets injected into intracluster medium and associated flow dynamics, such as shocks, velocity shear, turbulence, through three-dimensional relativistic hydrodynamic (RHD) simulations. To that end, we have developed a high-order accurate RHD code, equipped with weighted essentially non-oscillatory scheme realistic equation state. Using explore set jet models parameters relevant to FR-II radio galaxies. confirm overall morphology is primarily determined by power, jet-to-background density pressure ratios play secondary roles. Jets higher powers propagate faster, resulting in more elongated structures, while those lower produce extended cocoons. Shear interfaces are dynamically unstable, hence, chaotic shocks turbulence develop. find fraction jet-injected energy dissipated greater less powerful jets, although actual amount larger jets. In power backflow dominant dissipation owing broad cocoon filled turbulence. contrast, both jet-spine important for dissipation. Our results imply different mechanisms, diffusive shock acceleration, shear stochastic turbulent may be involved production ultra-high cosmic rays