English
Related papers

Related papers: Finding Wolf-Rayet Stars in the Local Group

200 papers

Wolf-Rayet (WR) stars, as they are advanced stages of the life of massive stars, provide a good test for various physical processes involved in the modelling of massive stars, such as rotation and mass loss. In this paper, we show the…

Solar and Stellar Astrophysics · Physics 2015-08-20 Cyril Georgy , Sylvia Ekström , Raphael Hirschi , Georges Meynet , José Groh , Patrick Eggenberger

Wolf-Rayet (WR) stars comprise a class of stars whose spectra are dominated by strong, broad emission lines that are associated with copious mass loss. In the massive-star regime, roughly 90% of the known WR stars are thought to have…

Solar and Stellar Astrophysics · Physics 2024-11-20 Tomer Shenar

The majority of Wolf-Rayet (WR) stars represent the stripped cores of evolved massive stars who lost most of their hydrogen envelope. In low metallicity environments, such as the Small Magellanic Cloud (SMC), stellar winds are weaker and…

Solar and Stellar Astrophysics · Physics 2018-04-04 Abel Schootemeijer , Norbert Langer

We conducted an extensive search for Wolf-Rayet stars (W-Rs) in the SMC, using the same interference filter imaging techniques that have proved successful in finding W-Rs in more distant members of the Local Group. Photometry of some 1.6…

Astrophysics · Physics 2009-10-31 Phil Massey , Alaine Duffy

(Abridged) We perform a comprehensive multiwavelength analysis of a sample of 20 starburst galaxies that show the presence of a substantial population of Wolf-Rayet (WR) stars. In this paper we present the analysis of the O and WR star…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Angel R. Lopez-Sanchez , Cesar Esteban

We report the first-ever discovery of an extragalactic Wolf-Rayet (WR)star with Spitzer. A new WR star in the Large Magellanic Cloud (LMC) was revealed via detection of its circumstellar shell using 24 {\mu}m images obtained in the…

Solar and Stellar Astrophysics · Physics 2011-10-05 V. V. Gvaramadze , A. -N. Chené , A. Y. Kniazev , O. Schnurr

Wolf-Rayet stars (WRs) are one of the final evolutionary stages of massive stars and immediate progenitors of stellar-mass black holes. Their multiplicity forms an important anchor point in single and binary population models for predicting…

Massive Wolf-Rayet (WR) stars dominate the radiative and mechanical energy budget of galaxies and probe a critical phase in the evolution of massive stars prior to core-collapse. It is not known whether core He-burning WR stars (classical…

We combine new CCD UBV photometry and spectroscopy with that from the literature to investigate 19 Magellanic Cloud OB associations that contain Wolf-Rayet (WR) and other types of evolved massive stars. Our spectroscopy reveals a wealth of…

Astrophysics · Physics 2009-10-31 Philip Massey , Elizabeth Waterhouse , Kathleen DeGioia-Eastwood

The total population of Wolf-Rayet (WR) stars in the Galaxy is predicted by models to be as many as $\sim$6000 stars, and yet the number of catalogued WR stars as a result of optical surveys was far lower than this ($\sim$200) at the turn…

Solar and Stellar Astrophysics · Physics 2015-09-11 A. P. Marston , J. Mauerhan , P. Morris , S. Van Dyk

We report the results of an intense, spectroscopic survey of all 41 late-type, nitrogen-rich Wolf-Rayet (WR) stars in the Large Magellanic Cloud (LMC) observable with ground-based telescopes. This survey concludes the decade-long effort of…

Astrophysics · Physics 2009-11-13 O. Schnurr , A. F. J. Moffat , N. St-Louis , N. I. Morrell , M. A. Guerrero-Roncel

We report the discovery of fifteen previously unknown Wolf-Rayet (WR) stars found as part of an infrared broad-band study of candidate WR stars in the Galaxy. We have derived an empirically-based selection algorithm which has selected ~5000…

Astrophysics · Physics 2008-11-26 L. J. Hadfield , S. D. Van Dyk , P. W. Morris , J. D. Smith , A. P. Marston , D. E. Peterson

Wolf-Rayet stars are evolved massive stars, and the relative number of WC-type and WN-type WRs should vary with the metallicity of the host galaxy, providing a sensitive test of stellar evolutionary theory. However, past studies of the WR…

Solar and Stellar Astrophysics · Physics 2015-06-11 Kathryn F. Neugent , Philip Massey , Cyril Georgy

Wolf-Rayet (WR) stars are the evolved descendants of the most massive stars and show emission-line dominated spectra formed in their powerful stellar winds. Marking the final evolution stage before core collapse, the standard picture of WR…

Wolf-Rayet stars have been detected in a large number of galaxies experiencing intense bursts of star formation. All stars initially more massive than a certain, metallicity-dependent, value are believed to experience the Wolf-Rayet phase…

Astrophysics · Physics 2009-10-31 J. Miguel Mas-Hesse , Daniel Kunth , Miguel Cervino

Massive Wolf-Rayet (WR) stars comprise a spectroscopic class characterized by high temperatures (Teff > ~30 kK) and powerful and rapid stellar winds. Hydrogen-rich WR stars represent the most massive stars in existence (M > ~100 Msun),…

Solar and Stellar Astrophysics · Physics 2024-10-15 Tomer Shenar

We are continuing a J, K and narrow-band imaging survey of 300 square degrees of the plane of the Galaxy, searching for new Wolf-Rayet stars. Our survey spans 150 degrees in Galactic longitude and reaches 1 degree above and below the…

Here we examine 12 Galactic clusters and OB associations containing Wolf-Rayet stars (W-Rs) and/or Luminous Blue Variables (LBVs), in order to assess the progentor masses of these evolved massive stars. We find that in the Milky Way,…

Astrophysics · Physics 2009-10-31 P. Massey , K. DeGioia-Eastwood , E. Waterhouse

CONTEXT: Very massive stars pass through the Wolf-Rayet (WR) stage before they finally explode. Details of their evolution have not yet been safely established, and their physics are not well understood. Their spectral analysis requires…

Astrophysics · Physics 2009-11-11 W. -R. Hamann , G. Graefener , A. Liermann

The discovery of new Wolf-Rayet (WR) stars in our Galaxy via large-scale narrowband optical surveys has been severely limited by dust extinction. Recent improvements in infrared technology have made narrowband-broadband imaging surveys…