Simulation of relativistic shocks and associated radiation from turbulent magnetic fields

Using our new 3‐D relativistic particle‐in‐cell (PIC) code, we investigated long‐term particle acceleration associated with a relativistic electron‐positron jet propagating in an unmagnetized ambient electron‐positron plasma. The simulations were performed using a much longer simulation system than our previous simulations in order to investigate the full nonlinear stage of the Weibel instability and its particle acceleration mechanism. Cold jet electrons are thermalized and ambient electrons are accelerated in the resulting shocks. Acceleration of ambient electrons leads to a maximum ambient electron density three times larger than the original value as predicted by hydrodynamic compression. Behind the bow shock, in the jet shock, strong electromagnetic fields are generated. These fields may lead to time dependent afterglow emission. In order to go beyond the standard synchrotron model used in astrophysical objects we have used PIC simulations and calculated radiation based on first principles. We calcul...