Bibcode
García, M.; Herrero, A.; Najarro, F.; Lennon, D. J.; Urbaneja, M. A.
Bibliographical reference
New windows on massive stars: asteroseismology, interferometry, and spectropolarimetry, Proceedings of the International Astronomical Union, IAU Symposium, Volume 307, pp. 41-46
Advertised on:
1
2015
Citations
1
Refereed citations
1
Description
In the race to break the SMC frontier and reach metallicity conditions
closer to the First Stars the information from UV spectroscopy is
usually overlooked. New HST-COS observations of OB stars in the
metal-poor galaxy IC1613, with oxygen content ~1/10 solar, have proved
the important role of UV spectroscopy to characterize blue massive stars
and their winds. The terminal velocities (υ∞) and
abundances derived from the dataset have shed new light on the problem
of metal-poor massive stars with strong winds. Furthermore, our results
question the υ∞-υ esc and
υ∞-Z scaling relations whose use in optical-only
studies may introduce large uncertainties in the derived mass loss rates
and wind-momenta. Finally, our results indicate that the detailed
abundance pattern of each star may have a non-negligible impact on its
wind properties, and scaling these as a function of one single
metallicity parameter is probably too coarse an approximation.
Considering, for instance, that the [α/Fe] ratio evolves with the
star formation history of each galaxy, we may be in need of updating all
our wind recipes.