Inflating fat bubbles in clusters of galaxies by precessing massive slow jets

We conduct hydrodynamical numerical simulations and find that precessing massive slow jets can inflate fat bubbles, that is, more- or less-spherical bubbles, that are attached to the centre of clusters of galaxies. To inflate a fat bubble, the jet should precess fast. The precessing angle θ should be large, or change over a large range 0 ≤ θ ≤ θ_max ∼ 30°-70° (depending also on other parameters), where θ = 0° is the symmetry axis. The constraints on the velocity and mass-outflow rate are similar to those on wide jets to inflate fat bubbles. The velocity should be v_j ∼ 10⁴ km s^-1, and the mass-loss rate of the two jets should be. These results, and our results from a previous paper dealing with slow wide jets, support the claim that a large fraction of the feedback heating in cooling flow clusters and in the processes of galaxy formation is done by slow massive jets.