On the nature of WO stars: a quantitative analysis of the WO3 star DR1 in IC 1613 ?

  title={On the nature of WO stars: a quantitative analysis of the WO3 star DR1 in IC 1613 ?},
  author={Frank Tramper and Gotz Grafener and Olga E. Hartoog and Hugues Sana and Alex de Koter and Jacco Vink and Lucas E. Ellerbroek and Norbert Langer and M. Garcia and Lex Kaper and Selma E. de Mink},
  journal={Astronomy and Astrophysics},
Context. Oxygen sequence Wolf-Rayet (WO) stars are thought to represent the final evolutionary stage of the most massive stars. The characteristic strong Ovi emission possibly originates from an enhanced oxygen abundance in the stellar wind. Alternatively, the Ovi emission can be caused by the high temperature of these stars, in which case the WO stars are the high-temperature extension of the more common carbon sequence Wolf-Rayet (WC) stars. Aims. By constraining the physical properties and… 

Massive stars on the verge of exploding: the properties of oxygen sequence Wolf-Rayet stars

Context. Oxygen sequence Wolf-Rayet (WO) stars represent a very rare stage in the evolution of massive stars. Their spectra show strong emission lines of helium-burning products, in particular highly

WO-type Wolf–Rayet Stars: The Last Hurrah of Massive Star Evolution

Are WO-type Wolf–Rayet (WR) stars in the final stage of massive star evolution before core-collapse? Although WC- and WO-type WRs have very similar spectra, WOs show a much stronger O vi λλ3811,34

The properties of low-metallicity massive stars

My thesis has two main topics: the study of low-metallicity massive stars, and the study of the suspected final stage of massive stars from a certain initial mass range, the WO stars. All the data

Helium Stars: Towards an Understanding of Wolf-Rayet Evolution

Wolf-Rayet (WR) stars are massive stars that have lost most or all of their hydrogen via powerful stellar winds. Recent observations have indicated that hydrogen-free WR stars have cooler

Low-metallicity massive single stars with rotation

Context. Metal-poor massive stars are assumed to be progenitors of certain supernovae, gamma-ray bursts, and compact object mergers that might contribute to the early epochs of the Universe with

The MiMeS Survey of Magnetism in Massive Stars: CNO surface abundances of Galactic O stars

The evolution of massive stars is still partly unconstrained. Mass, metallicity, mass loss and rotation are the main drivers of stellar evolution. Binarity and magnetic field may also significantly

Wolf-Rayet stars in the Small Magellanic Cloud: II. Analysis of the binaries

Massive WR stars are evolved massive stars characterized by strong mass-loss. Hypothetically, they can form either as single stars or as mass donors in close binaries. About 40% of the known WR stars

The properties of single WO stars

Abstract 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 the WO


We present a new empirical prescription for the mass-loss rates of carbon- and oxygen-sequence Wolf–Rayet stars as a function of their luminosity, surface chemical composition, and initial

The Wolf–Rayet Content of the Galaxies of the Local Group and Beyond

Wolf–Rayet stars (WRs) represent the end of a massive star’s life as it is about to turn into a supernova. Obtaining complete samples of such stars across a large range of metallicities poses



New Models for Wolf-Rayet and O Star Populations in Young Starbursts

Using the latest stellar evolution models, theoretical stellar spectra, and a compilation of observed emission line strengths from Wolf-Rayet (W-R) stars, we construct evolutionary synthesis models

Quantitative classification of WC and WO stars

We present a quantitative classification scheme for carbon and oxygen sequence Wolf-Rayet stars. Our scheme uses new high-quality optical AAT and INT observations of 20 stars for which we provide

The Galactic WC stars Stellar parameters from spectral analyses indicate a new evolutionary sequence

[Abridged] [...] AIMS: We aim to establish the stellar parameters and mass-loss rates of the Galactic WC stars. These data provide the empirical basis of studies of (i) the role of WC stars in the

Stellar and wind properties of LMC WC4 stars A metallicity dependence for Wolf-Rayet mass-loss rates ?

We use ultraviolet space-based (FUSE, HST) and optical/IR ground-based (2.3 m MSSSO, NTT) spectroscopy to determine the physical parameters of six WC4-type Wolf-Rayet stars in the Large Magellanic

Stellar evolution with rotation X: Wolf-Rayet star populations at solar metallicity

We examine the properties of Wolf-Rayet (WR) stars predicted by models of rotating stars taking account of the new mass loss rates for O-type stars and WR stars (Vink et al. 2000. 2001; Nugis &


While observing OB stars within the most crowded regions of the Large Magellanic Cloud, we happened upon a new Wolf–Rayet (WR) star in Lucke–Hodge 41, the rich OB association that contains S Doradus

Constraints on the Evolution of Massive Stars through Spectral Analysis. I. The WC5 Star HD 165763

Using a significantly revised non-LTE radiative transfer code that allows for the effects of line blanketing by He, C, O, Si, and Fe, we have performed a detailed analysis of the Galactic Wolf-Rayet

Mass loss from late-type WN stars and its Z-dependence: very massive stars approaching the Eddington limit

The mass loss from Wolf-Rayet (WR) stars is of fundamental importance for the final fate of massive stars and their chemical yields. Its Z-dependence is discussed in relation to the formation of


Observations of an H II region in IC 1613 which is excited by a hot Wolf-Rayet star are reported, and the nebular and stellar spectra are discussed. The nebular helium abundance is not far above the

The Young Stellar Population of IC1613. I. A New Catalogue of OB Associations

Context: Determining the parameters of massive stars is crucial to understand many processes in galaxies and the Universe, since these objects are important sources of ionization, chemical enrichment