High-resolution three-dimensional simulations of relativistic jets

We have performed high-resolution three-dimensional simulations of relativi stic jets with beam-how Lorentz factors of up to 7, a spatial resolution of 8 cells per beam radius, and up to 75 normalized time units in order to st udy the morphology and dynamics of three-dimensional relativistic jets. Our simulations show that the coherent fast backflows found in axisymmetric mo dels are not present in three-dimensional models. We further find that when the jet is exposed to nonaxisymmetric perturbations, (1) it does not displ ay the strong perturbations found for three-dimensional classical hydrodyna mic and MHD jets (at least during the period of time covered by our simulat ions) and (2) it does propagate according to the one-dimensional estimate. Small three-dimensional effects in the relativistic beam give rise to a lum py distribution of apparent speeds like that observed in M87. The beam is s urrounded by a boundary layer of high specific internal energy. The propert ies of this layer are briefly discussed.