Simulations of unstable recollimation shocks

3D relativistic (magneto)hydrodynamical simulations of the confinement of jets revealed that the jet-environment interface downstream of recollimation shocks is susceptible to instabilities that can be strong enough to destroy the jet structure and quickly decelerate it to sub-relativistic velocities. This is in contrast with the picture, supported by 2D, of confined jets undergoing a series of recollimation and reflection shocks. Motivated by the impact of such a different scenario on the evolution and radiation of jetted active galactic nuclei (AGNs), we investigate the stability at recollimation of relativistic AGN jets, by means of high resolution 3D hydrodynamical simulations, devoted to unveil the interplay among the various instabilities developing. In this work we show the results for a low-power unstable jet, compatible with the properties of Fanaroff-Riley type 0 radio-galaxies. We suggest that the differences between high- and low-power radio-galaxies, as well as differences among high-energy peaked blazars, could be interpreted as a transition between stable and unstable configurations.