Quantitative spectroscopy of Wolf—Rayet stars in HD 97950 and R136a — the cores of giant H ii regions

  title={Quantitative spectroscopy of Wolf—Rayet stars in HD 97950 and R136a — the cores of giant H ii regions},
  author={Paul A. Crowther and Luc Dessart},
  journal={Monthly Notices of the Royal Astronomical Society},
We present quantitative analyses of Wolf–Rayet stars in the cores of two giant H ii regions — HD 97950 in NGC 3603 and R136a in 30 Doradus — based on archive Hubble Space Telescope (HST) spectroscopy. We confirm previous WN6h+abs classifications for components A1, B and C in HD 97950, while classifications for R136a1–3 are revised from O3 If*/WN6 to WN5h. From detailed non-local thermodynamic equilibrium analyses, we find that all Wolf–Rayet stars exhibit products of CNO-processed material at… 
How extreme are the Wolf–Rayet clusters in NGC 3125?*
We reinvestigate the massive stellar content of the irregular dwarf galaxy NGC 3125 (Tol 3) using Very Large Telescope (VLT)/FORS1 imaging and spectroscopy, plus archival VLT/ISAAC, Hubble Space
The Wolf–Rayet binaries of the nitrogen sequence in the Large Magellanic Cloud
Context. 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
The Wolf-Rayet stars in the Large Magellanic Cloud - A comprehensive analysis of the WN class
Context. Massive stars, although being important building blocks of galaxies, are still not fully understood. This especially holds true for Wolf-Rayet (WR) stars with their strong mass loss, whose
Searching for hidden Wolf–Rayet stars in the Galactic plane – 15 new Wolf–Rayet stars
We report the discovery of 15 previously unknown Wolf–Rayet (WR) stars found as part of an infrared (IR) broad-band study of candidate WR stars in the Galaxy. We have derived an empirically based
The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables Determined from Cluster Turnoffs. II. Results from 12 Galactic Clusters and OB Associations
In a previous paper on the Magellanic Clouds, we demonstrated that coeval clusters provide a powerful tool for probing the progenitor masses of Wolf-Rayet (W-R) stars and luminous blue variables
Hydrogen in the atmosphere of the evolved WN3 Wolf–Rayet star WR 3: defying an evolutionary paradigm?
WR 3 is the brightest very early-type WN star in the sky. Based on several years of timeresolved spectroscopy and precision photometry on various time-scales, we deduce that WR 3 is most likely a
A Very Large Telescope imaging and spectroscopic survey of the Wolf–Rayet population in NGC 7793*
We present a Very Large Telescope/Focal Reducer and Low Dispersion Spectrograph #1 (VLT/FORS1) imaging and spectroscopic survey of the Wolf-Rayet (WR) population in the Sculptor group spiral galaxy
Gemini observations of Wolf-Rayet stars in the Local Group starburst galaxy IC 10
We present Gemini-N GMOS and CFHT MOS spectroscopy of Wolf-Rayet candidates in the Local Group dwarf galaxy IC 10 that were previously identified by Massey et al. and Royer et al. From the present
Unlocking Galactic Wolf–Rayet stars with Gaia DR2 – I. Distances and absolute magnitudes
We obtain distances to 383 Galactic Wolf–Rayet (WR) stars from Gaia DR2 parallaxes and Bayesian methods, with a prior based on H ii regions and dust extinction. Distances agree with those from
Reduced Wolf-Rayet line luminosities at low metallicity
New NTT/EMMI spectrophotometry of single WN2–5 stars in the Small and Large Magellanic Clouds are presented, from which He ii  λ 4686 line luminosities have been derived, and compared with