3D Hydrodynamic Simulations of Large-Scale Precessing Jets: Radio
  Morphology
  The prospect of relativistic jets exhibiting complex morphologies as a
consequence of geodetic precession has long been hypothesised. We have carried
out a 3D hydrodynamics simulation study varying the precession cone angle, jet
injection speed and number of turns per simulation time. Using proxies for the
radio emission we project the sources with different inclinations to the line
of sight to the observer. We find that a number of different precession
combinations result in characteristic `X' shaped sources which are frequently
observed in radio data, and some precessing jet morphologies may mimic the
morphological signatures of restarting radio sources. We look at jets ranging
in scale from tens to hundreds of kiloparsecs and develop tools for identifying
known precession indicators of point symmetry, curvature and jet misalignment
from the lobe axis and show that, based on our simulation sample of precessing
and non-precessing jets, a radio source that displays any of these indicators
has a 98% chance of being a precessing source.
