1996A&A...313..897A

We present a time-dependent hydrodynamic model for the Wolf-Rayet ring nebula RCW 58 that includes a self-consistent treatment of the nonequilibrium evolution of the ionisation state of the gas. We investigate the feasibility that hydrodynamic ablation from embedded dense clumps in the nebula is responsible for the high-velocity ultraviolet absorption features observed towards the central star. It is found that the observed correlation between the velocity of these features and the ionisation potential of the absorbing ion can be qualitatively reproduced by such a model. The calculated velocity range depends strongly on the adopted wind velocity.