TY  - GEN
A1  - Vink, Jorick Sandor
A1  - Heger, Alexander
A1  - Krumholz, Mark R.
A1  - Puls, Joachim
A1  - Banerjee, Shiladitya
A1  - Castro, Norberto
A1  - Chen, K.-J.
A1  - Chenè, A.-N.
A1  - Crowther, P. A.
A1  - Daminelli, A.
A1  - Gräfener, G.
A1  - Groh, J. H.
A1  - Hamann, Wolf-Rainer
A1  - Heap, S.
A1  - Herrero, A.
A1  - Kaper, L.
A1  - Najarro, F.
A1  - Oskinova, Lida
A1  - Roman-Lopes, A.
A1  - Rosen, A.
A1  - Sander, A.
A1  - Shirazi, M.
A1  - Sugawara, Y.
A1  - Tramper, F.
A1  - Vanbeveren, D.
A1  - Voss, R.
A1  - Wofford, A.
A1  - Zhang, Y.
T1  - Very massive stars in the local universe
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - Recent studies have claimed the existence of very massive stars (VMS) up to 300 M⊙ in the local Universe. As this finding may represent a paradigm shift for the canonical stellar upper-mass limit of 150 M⊙, it is timely to discuss the status of the data, as well as the far-reaching implications of such objects. We held a Joint Discussion at the General Assembly in Beijing to discuss (i) the determination of the current masses of the most massive stars, (ii) the formation of VMS, (iii) their mass loss, and (iv) their evolution and final fate. The prime aim was to reach broad consensus between observers and theorists on how to identify and quantify the dominant physical processes.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 601 
KW  - stars: massive stars
KW  - stars: mass-loss
KW  - stars: stellar evolution
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-415220
SN  - 1866-8372
IS  - 601
ER  - 
TY  - JOUR
A1  - Fryer, C. L.
A1  - Langer, Norbert
A1  - Heger, Alexander
A1  - Wellstein, Stephan
T1  - The limiting stellar initial mass for black hole formation in close binary
N2  - We present models for the complete life and death of a 60 Msolar star evolving in a close binary system, from the main-sequence phase to the formation of a compact remnant and fallback of supernova debris. After core hydrogen exhaustion, the star expands, loses most of its envelope by Roche lobe overflow, and becomes a Wolf-Rayet star. We study its post-mass transfer evolution as a function of the Wolf-Rayet wind mass-loss rate (which is currently not well constrained and will probably vary with the initial metallicity of the star). Varying this mass-loss rate by a factor of 6 leads to stellar masses at collapse that range from 3.1 up to 10.7 Msolar. Because of different carbon abundances left by core helium burning and nonmonotonic effects of the late shell-burning stages as function of the stellar mass, we find that, although the iron core masses at collapse are generally larger for stars with larger final masses, they do not depend monotonically on the final stellar mass or even the C/O core mass. We then compute the evolution of all models through collapse and bounce. The results range from strong supernova explosions (Ekin>1051ergs) for the lower final masses to the direct collapse of the star into a black hole for the largest final mass. Correspondingly, the final remnant masses, which were computed by following the supernova evolution and fallback of material for a timescale of about one year, are between 1.2 and 10 Msolar. We discuss the remaining uncertainties of this result and outline the consequences of our results for the understanding of the progenitor evolution of X-ray binaries and gamma-ray burst models.
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Heger, Alexander
A1  - Woosley, S. E.
A1  - Langer, Norbert
T1  - Stellar models including pre-SN/SN phases
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Heger, Alexander
A1  - Langer, Norbert
A1  - Woosley, S. E.
T1  - Presupernova evolution of rotating massive stars I : numerical method and evolution of the internal stellar structure
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Langer, Norbert
A1  - Heger, Alexander
T1  - Massive star evolution
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Langer, Norbert
A1  - Heger, Alexander
A1  - Wellenstein, Stephan
A1  - Herwig, Falk
T1  - Mixing and nucleosynthesis in rotating TP-AGB stars
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Langer, Norbert
A1  - Heger, Alexander
T1  - Evolution and explosion of Wolf-Rayet stars
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Langer, Norbert
A1  - Heger, Alexander
A1  - Garcia-Segura, Guillermo
T1  - Massive stars : the pre-supernova evolution of internal and circumstellar structure
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Heger, Alexander
A1  - Langer, Norbert
A1  - Woosley, S. E.
T1  - Nucleosynthesis in rotating massive stars
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Langer, Norbert
A1  - Heger, Alexander
A1  - Braun, H.
T1  - Nucleosynthesis in massive stars
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Langer, Norbert
A1  - Heger, Alexander
T1  - B[e] supergiants : what is their evolutionary status?
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Heger, Alexander
A1  - Langer, Norbert
T1  - The spin-up of contracting red supergiants
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Langer, Norbert
A1  - Fliegner, J.
A1  - Heger, Alexander
A1  - Woosley, S. E.
T1  - Nucleosynthesis in rotating massive stars
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Heger, Alexander
A1  - Jeannin, Laurent
A1  - Langer, Norbert
A1  - Baraffe, Isabelle
T1  - Pulsations in red supergiants with high L/M ratio : implications for the stellar and circumstellar structure of supernova progenitors
Y1  - 1997
ER  -