Large Scale Simulations of the Jet-Igm Interaction

In a parameter study extending to jet densities of 10−5 times the ambient one, I have recently shown that light large-scale jets start their lives in a spherical bow shock phase. This allows an easy description of the sideways bow shock propagation in that phase. Here, I present new, bipolar, simulations of very light jets in 2.5D and 3D, reaching the observationally relevant scale of > 200 jet radii. Deviations from the early bow shock propagation law are expected because of various effects. The net effect is, however, shown to remain small. I calculate the X-ray appearance of the shocked cluster gas and compare it with Cygnus A and 3C 317. Rings, bright spots and enhancements inside the radio cocoon may be explained.