Other
Scientific paper
Jul 1991
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1991hst..prop.2581b&link_type=abstract
HST Proposal ID #2581
Other
Hst Proposal Id #2581
Scientific paper
We propose to study the stellar wind characteristics of hot massive stars in M31 and M33 by observing with the HST-FOS the profiles of UV resonance lines which are the main wind indicators. The immediate aim is to understand how mass loss rates, and other characteristics of the stellar winds, such as the velocity-laws (i.e. the acceleration) and the ionization, depend on metallicity. The final goal is to understand the evolution of massive stars in galaxies of different chemical composition. The dependence of hot star winds on metallicity is in fact predicted by the theory of radiation-pressure driven winds, but it could be observed so far only in the MCs stars (Hutchings, 1982; Garmany and Conti 1985; Kudritzski et al, 1987). In the past years we have pushed IUE to its limits to observe far UV spectra of the brightest/hottest stars in M31 and M33. In spite of the very low resolution (insufficent for quantitative line analysis) we observed for all the stars of our sample significantly lower terminal velocities and weaker P Cygni profiles than for galactic stars of similar type. The results of this pioneer study (that involved also an extensive ground based observing program) on one hand, and the recent significant improvements of the radiation driven wind theory and treatment of ionization equilibrium in the stellar atmospheres and envelopes on the other hand, show that a higher resolution study of the UV lines will be very interesting.
No associations
LandOfFree
Stellar Winds of Massive Stars in Nearby Galaxies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Stellar Winds of Massive Stars in Nearby Galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stellar Winds of Massive Stars in Nearby Galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-862508