Modeling the Lyα radiation of high-redshift galaxies

The Lyalpha line emission of high-redshift galaxies depends on the density and temperature distribution of the gas, the kinematics and the dust content. We use a finite element method to model the Lyalpha radiation of different 3D configurations considering complete frequency redistribution and the influence of velocity fields. Our results show that the central absorption feature of the double-peaked Lyalpha line profile observed in many radio galaxies with z = 2- 4 is probably the consequence of frequency redistribution rather than foreground absorption. The blue peak of the profile is enhanced for models with infall motion and the red peak for models with outflow motion. In particular, we attempt to model the extended Lyalpha emission of high-redshift radio galaxies, where we consider results of corresponding hydrodynamical simulations to select possible model configurations. We find that Lyalpha photons scattered outside a jet-influenced low-density region are able to produce an extended Lyalpha halo.