Properties of jets at different scales and the connection with accretion

Results of a Chandra/HST survey for resolved high frequency emission from radio bright AGN jets are summarized. The multifrequency mapping and modelling indicates that powerful jets generally remain relativistic up to very large scales (10(22-24) cm). The X-ray to radio flux ratios of emission "knots" along the large scale jets are found to decrease systematically, which can be interpreted as moderate deceleration of the bulk flow near the jet end. In two cases the physical parameters and kinetic power at large scales can be compared with those deduced in a consistent way for the blazar emission region (10(16-17) CM) suggesting that the propagation is essentially free with little power dissipation between the two scales. Finally, connecting the jet properties with those of the presumed associated accretion disk (10(14-15) cm) a unified scenario is suggested whereby the most powerful jets are produced by rapidly spinning black holes with bright, near Eddington accretion disks. Significantly lower accretion rates (in Eddington units) lead to jets of lower absolute power and very underluminous disks (as predicted in ADAF-like models) thus with a higher ratio of jet to disk luminosity.