Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-25T04:23:13.838Z Has data issue: false hasContentIssue false

Massive stars near the Eddington-limit, pulsations & mass-loss

Published online by Cambridge University Press:  23 January 2015

G. Gräfener*
Affiliation:
Armagh Observatory, College Hill, Armagh, BT61 9DG, United Kingdom
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Very massive stars (in excess of ~ 100 M) and massive stars in pre-SN phases at the end of their evolution are continuously approaching the Eddington limit. According to our theoretical predictions their high Eddington factors lead to a peculiar sub-photospheric structure and enhanced mass-loss. Their proximity to the Eddington limit is thus likely the reason why these objects appear as LBVs and WR stars. Here we discuss how our predictions relate to the characteristics of strange-mode pulsations, and how rotating massive stars at low metallicities can produce spectroscopic signatures that have recently been observed in a sample of star-forming galaxies at redshifts z ≈ 2 – 4.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2015 

References

Bestenlehner, J. M., Gräfener, G., Vink, J. S., et al. 2014, A&A, submittedGoogle Scholar
Cantiello, M., Langer, N., Brott, I., et al. 2009, A&A 499, 279Google Scholar
Cassata, P., Le Fèvre, O., Charlot, S., et al. 2013, A&A 556, A68Google Scholar
Crowther, P. A., Schnurr, O., Hirschi, R., et al. 2010, MNRAS 408, 731Google Scholar
Glatzel, W. 2008, in Werner, A. & Rauch, T. (ed.), Hydrogen-deficient stars, Vol. 391 of Astronomical Society of the Pacific Conference Series, p. 307, San Francisco: Astronomical Society of the PacificGoogle Scholar
Glatzel, W. 2009, Communications in Asteroseismology 158, 252Google Scholar
Glatzel, W. & Kaltschmidt, H. O. 2002, MNRAS 337, 743Google Scholar
Gräfener, G. & Hamann, W.-R. 2008, A&A 482, 945Google Scholar
Gräfener, G., Owocki, S. P., & Vink, J. S. 2012a, A&A 538, A40Google Scholar
Gräfener, G., Vink, J. S., de Koter, A., & Langer, N. 2011, A&A 535, A56Google Scholar
Gräfener, G., Vink, J. S., Harries, T. J., & Langer, N. 2012b, A&A 547, A83Google Scholar
Groh, J. H., Hillier, D. J., Damineli, A., et al. 2009, ApJ 698, 1698Google Scholar
Hamann, W.-R., Gräfener, G., & Liermann, A. 2006, A&A 457, 1015Google Scholar
Hamann, W.-R. & Koesterke, L. 1998, A&A 335, 1003Google Scholar
Ishii, M., Ueno, M., & Kato, M. 1999, PASJ 51, 417CrossRefGoogle Scholar
Meynet, G. & Maeder, A. 2002, A&A 390, 561Google Scholar
Petrovic, J., Pols, O., & Langer, N. 2006, A&A 450, 219Google Scholar
Saio, H., Baker, N. H., & Gautschy, A. 1998, MNRAS 294, 622Google Scholar
Sander, A., Hamann, W.-R., & Todt, H. 2012, A&A 540, A144Google Scholar
Vink, J. S., Muijres, L. E., Anthonisse, B., et al. 2011, A&A 531, A132Google Scholar