Advances in radiatively driven wind models

PULS, J.; REPOLUST, T.; HOFFMAN, T.; JOKUTHY, A.; VENERO, R.

Lanzarote

Congreso; A Massive Star Odyssey: From Main Sequence to Supernova, Proceedings of IAU Symposium 212; 2001

IAU

We report on a re-analysis of the Galactic O-type star sample presented by Puls et al. (1996) by means of non-LTE model atmospheres including line-blocking and line-blanketing. In particular, we concentrate on the question concerning the dependence of the wind-momentum luminosity relation (WLR) on luminosity class. Owing to the line-blanketing, the derived effective temperatures become significantly lower when compared to previous results, whereas the so-called `modified wind-momentum rates´ remain roughly at their former values. Therefore, we obtain a new WLR for O-type stars. By comparing these `observational´ results with new theoretical predictions and simulations, we conclude that the Há forming region for objects with Há in emission might be considerably clumped and thus a larger mass-loss rate than actually present is mimicked. We suggest that the previously found dependence of the WLR on luminosity class is an artefact.