Three-dimensional magnetohydrodynamical simulations of the morphology of
  head-tail radio galaxies based on magnetic tower jet model
  The distinctive morphology of head-tail radio galaxies reveals strong
interactions between the radio jets and their intra-cluster environment, the
general consensus on the morphology origin of head-tail sources is that radio
jets are bent by violent intra-cluster weather. We demonstrate in this paper
that such strong interactions provide a great opportunity to study the jet
properties and also the dynamics of intra-cluster medium (ICM). By
three-dimensional magnetohydrodynamical simulations, we analyse the detailed
bending process of a magnetically dominated jet, based on the magnetic tower
jet model. We use stratified atmospheres modulated by wind/shock to mimic the
violent intra-cluster weather. Core sloshing is found to be inevitable during
the wind-cluster core interaction, which induces significant shear motion and
could finally drive ICM turbulence around the jet, making it difficult for jet
to survive. We perform detailed comparison between the behaviour of pure
hydrodynamical jets and magnetic tower jet, and find that the jet-lobe
morphology could not survive against the violent disruption in all of our pure
hydrodynamical jet models. On the other hand, the head-tail morphology is well
reproduced by using a magnetic tower jet model bent by wind, in which
hydrodynamical instabilities are naturally suppressed and the jet could always
keep its integrity under the protection of its internal magnetic fields.
Finally, we also check the possibility for jet bending by shock only. We find
that shock could not bend jet significantly, so could not be expected to
explain the observed long tails in head-tail radio galaxies.
