328 citations · 3.4k across the 37 of their papers we have counts for
37 papers
Physics and evolution of the most massive stars in 30 Dor. Mass loss, envelope inflation, and a variable upper stellar mass limit
Götz Gräfener
The identification of stellar-mass black-hole mergers with up to 80 Msun as powerful sources of gravitational wave radiation led to increased interest in the physics of the most ma…
The R136 star cluster dissected with Hubble Space Telescope/STIS. II. Physical properties of the most massive stars in R136
Joachim M. Bestenlehner, Paul A. Crowther, Saida M. Caballero-Nieves +11
We present an optical analysis of 55 members of R136, the central cluster in the Tarantula Nebula of the Large Magellanic Cloud. Our sample was observed with STIS aboard the Hubble…
Type Ia supernovae from non-accreting progenitors
John Antoniadis, Savvas Chanlaridis, Götz Gräfener +1
Type Ia supernovae (SNe Ia) are manifestations of stars deficient of hydrogen and helium disrupting in a thermonuclear runaway. While explosions of carbon-oxygen white dwarfs are t…
WR 72: a born-again planetary nebula with hydrogen-poor knots
V. V. Gvaramadze, A. Y. Kniazev, G. Graefener +1
We report the discovery of a handful of optical hydrogen-poor knots in the central part of an extended infrared nebula centred on the [WO1] star WR 72, obtained by spectroscopic an…
A massive white-dwarf merger product before final collapse
V. V. Gvaramadze, G. Gräfener, N. Langer +4
Gravitational wave emission can lead to the coalescence of close pairs of compact objects orbiting each other. For the case of neutron stars such mergers may yield masses above the…
The Galactic WN stars revisited. Impact of Gaia distances on fundamental stellar parameters
W. -R. Hamann, G. Gräfener, A. Liermann +6
Comprehensive spectral analyses of the Galactic Wolf-Rayet stars of the nitrogen sequence (i.e.\ the WN subclass) have been performed in a previous paper. However, the distances of…
The delay of shock breakout due to circumstellar material seen in most Type II Supernovae
F. Förster, T. J. Moriya, J. C. Maureira +35
Type II supernovae (SNe) originate from the explosion of hydrogen-rich supergiant massive stars. Their first electromagnetic signature is the shock breakout, a short-lived phenomen…
Response to comment on "An excess of massive stars in the local 30 Doradus starburst"
F. R. N. Schneider, H. Sana, C. J. Evans +29
Farr and Mandel reanalyse our data, finding initial-mass-function slopes for high mass stars in 30 Doradus that agree with our results. However, their reanalysis appears to underpr…
The VLT-FLAMES Tarantula Survey. XXIX. Massive star formation in the local 30 Doradus starburst
F. R. N. Schneider, O. H. Ramírez-Agudelo, F. Tramper +24
The 30 Doradus (30 Dor) nebula in the Large Magellanic Cloud (LMC) is the brightest HII region in the Local Group and a prototype starburst similar to those found in high redshift…
An excess of massive stars in the local 30 Doradus starburst
F. R. N. Schneider, H. Sana, C. J. Evans +29
The 30 Doradus star-forming region in the Large Magellanic Cloud is a nearby analogue of large star-formation events in the distant Universe. We determine the recent formation hist…
The VLT-FLAMES Tarantula Survey
Jorick S. Vink, C. J. Evans, J. Bestenlehner +5
We present a number of notable results from the VLT-FLAMES Tarantula Survey (VFTS), an ESO Large Program during which we obtained multi-epoch medium-resolution optical spectroscopy…
The Tarantula Massive Binary Monitoring project: II. A first SB2 orbital and spectroscopic analysis for the Wolf-Rayet binary R145
T. Shenar, N. D. Richardson, D. P. Sablowski +19
We present the first SB2 orbital solution and disentanglement of the massive Wolf-Rayet binary R145 (P = 159d) located in the Large Magellanic Cloud. The primary was claimed to hav…
The VLT-FLAMES Tarantula Survey XXV. Surface nitrogen abundances of O-type giants and supergiants
N. J. Grin, O. H. Ramirez-Agudelo, A. de Koter +19
Theoretically, rotation-induced chemical mixing in massive stars has far reaching evolutionary consequences, affecting the sequence of morphological phases, lifetimes, nucleosynthe…
The R136 star cluster dissected with Hubble Space Telescope/STIS. I. Far-ultraviolet spectroscopic census and the origin of HeII 1640 in young star clusters
Paul A. Crowther, S. M. Caballero-Nieves, K. A. Bostroem +17
We introduce a HST/STIS stellar census of R136a, the central ionizing star cluster of 30 Doradus. We present low resolution far-ultraviolet STIS/MAMA spectroscopy of R136 using 17…
Light-travel-time diagnostics in early Supernova spectra: substantial mass loss of the IIb progenitor of SN 2013cu through a superwind
G. Gräfener, J. S. Vink
The progenitors of type-IIb supernovae (SNe) are believed to have lost their H-rich envelopes almost completely in the direct pre-SN phase. Recently the first 'flash spectrum' of a…
Discovery of the massive overcontact binary VFTS 352: Evidence for enhanced internal mixing
L. A. Almeida, H. Sana, S. E. de Mink +15
The contact phase expected to precede the coalescence of two massive stars is poorly characterized due to the paucity of observational constraints. Here we report on the discovery…
Narrow He II emission in star-forming galaxies at low metallicity. Stellar wind emission from a population of Very Massive Stars
G. Gräfener, J. S. Vink
In a recent study star-forming galaxies with HeII emission between redshifts 2 and 4.6 have been found to occur in two modes, distinguished by the width of their HeII emission line…
The evolution of rotating very massive stars with LMC composition
K. Köhler, N. Langer, A. de Koter +8
We present a dense model grid with tailored input chemical composition appropriate for the Large Magellanic Cloud. We use a one-dimensional hydrodynamic stellar evolution code, whi…
Rotational velocities of single and binary O-type stars in the Tarantula Nebula
O. H. Ramírez-Agudelo, H. Sana, A. de Koter +15
Rotation is a key parameter in the evolution of massive stars, affecting their evolution, chemical yields, ionizing photon budget, and final fate. We determined the projected rotat…
The properties of single WO stars
F. Tramper, S. M. Straal, G. Gräfener +5
The enigmatic oxygen sequence Wolf-Rayet (WO) stars represent a very late stage in massive star evolution, although their exact nature is still under debate. The spectra of most of…
Very Massive Stars in the Local Universe
Jorick S. Vink
Recent studies suggest the existence of very massive stars (VMS) up to 300 solar masses in the local Universe. As this finding may represent a paradigm shift for the canonical stel…
On the H Behaviour of Blue Supergiants: Rise and Fall over the Bi-stability Jump
Blagovest Petrov, Jorick S. Vink, Götz Gräfener
The evolutionary state of blue supergiants is still unknown. Stellar wind mass loss is one of the dominant processes determining the evolution of massive stars, and it may provide…
The VLT-FLAMES Tarantula Survey XVI. The optical+NIR extinction laws in 30 Doradus and the photometric determination of the effective temperatures of OB stars
J. Maíz Apellániz, C. J. Evans, R. H. Barbá +11
Context: The commonly used extinction laws of Cardelli et al. (1989) have limitations that, among other issues, hamper the determination of the effective temperatures of O and earl…
The Wolf-Rayet stars in the Large Magellanic Cloud: A comprehensive analysis of the WN class
R. Hainich, U. Rühling, H. Todt +6
Aims: Following our comprehensive studies of the WR stars in the Milky Way, we now present spectroscopic analyses of almost all known WN stars in the LMC. Methods: For the quantita…