Effect of radiation reaction on slowdown in unmagnetized kinetic shocks

The slowdown of unmagnetized plasmas via the generation of kinetic shocks is studied using particle-in-cell (PIC) simulations in various parameter regimes.  The degree of slowdown caused by shocks generated by two cold interpenetrating pair plasmas is compared with that from shocks generated by a sharp boundary of a hot dense plasma and a colder tenuous plasma. In the first case, the slowdown is primarily caused by the generation of magnetic fields via the Weibel/ filamentation instability. In the second case, which can be realized in the lab using high-powered lasers interacting with near-solid density targets, an electrostatic shock is generated. Collisions between the electrostatic shocks also lead to magnetic fields via the Weibel instability.  The plasma's interaction with these electromagnetic fields is the major cause of slowdown.  However, with the most powerful lasers available today it may be possible that the electromagnetic fields and the energy of plasma become significantly large such that radiation reaction will begin to play an important role in the slowdown. We investigate the importance of the radiation reaction on the slowdown taking advantage of PIC simulations that self-consistently include the Landau Lifshitz radiation reaction forces on the plasma.