Massive stars in advanced evolutionary stages, and the progenitor of GW150914

التفاصيل البيبلوغرافية
العنوان: Massive stars in advanced evolutionary stages, and the progenitor of GW150914
المؤلفون: Hamann, Wolf-Rainer, Oskinova, Lidia, Todt, Helge, Sander, Andreas, Hainich, Rainer, Shenar, Tomer, Ramachandran, Varsha
سنة النشر: 2017
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Solar and Stellar Astrophysics
الوصف: The recent discovery of a gravitational wave from the merging of two black holes of about 30 solar masses each challenges our incomplete understanding of massive stars and their evolution. Critical ingredients comprise mass-loss, rotation, magnetic fields, internal mixing, and mass transfer in close binary systems. The imperfect knowledge of these factors implies large uncertainties for models of stellar populations and their feedback. In this contribution we summarize our empirical studies of Wolf-Rayet populations at different metallicities by means of modern non-LTE stellar atmosphere models, and confront these results with the predictions of stellar evolution models. At the metallicity of our Galaxy, stellar winds are probably too strong to leave remnant masses as high as 30 solar masses, but given the still poor agreement between evolutionary tracks and observation even this conclusion is debatable. At the low metallicity of the Small Magellanic Cloud, all WN stars which are (at least now) single are consistent with evolving quasi-homogeneously. O and B-type stars, in contrast, seem to comply with standard evolutionary models without strong internal mixing. Close binaries which avoided early merging could evolve quasi-homogeneously and lead to close compact remnants of relatively high masses that merge within a Hubble time.
Comment: 5 pages, to be published in the Proceedings of the IAU Symposium No. 329 "The lives and death-throes of massive stars"
نوع الوثيقة: Working Paper
DOI: 10.1017/S1743921317002563
URL الوصول: http://arxiv.org/abs/1702.05629
رقم الأكسشن: edsarx.1702.05629
قاعدة البيانات: arXiv
الوصف
DOI:10.1017/S1743921317002563