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The Galactic WN stars. Spectral analyses with line-blanketed model atmospheres versus stellar evolut
An infrared light-receiving device includes an optical absorption layer disposed on a principal surface of a substrate and an optical filter disposed on the optical absorption layer, the opticalExpand
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 theExpand
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 ofExpand
Early Magnetic B-Type Stars: X-ray Emission and Wind Properties
We present a comprehensive study of X-ray emission and wind properties of massive magnetic early B-type stars. Dedicated XMM-Newtonobservations were obtained for three early type B-type stars, ξ 1Expand
Macroclumping as solution of the discrepancy between Hα and P v mass loss diagnostics for O-type stars
Context. Recent studies of O-type stars have demonstrated that discrepant mass-loss rates are obtained when different diagnostic methods are employed. Fitting the unsaturated UV resonance linesExpand
Line-blanketed model atmospheres for WR stars
We describe the treatment of iron group line-blanketing in non-LTE model atmospheres for WR stars. As an example, a blanketed model for the early-type WC star WR 111 is compared to its un-blanketedExpand
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, whoseExpand
High-resolution X-ray spectroscopy of bright O-type stars
Archival X-ray spectra of the four prominent single, non-magnetic O stars ζ Pup, ζ Ori, ξ Per, ζ Oph, obtained in high resolution with Chandra HETGS/MEG have been studied. The resolved X-ray emissionExpand
The Galactic WN stars revisited. Impact of Gaia distances on fundamental stellar parameters
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 these objects wereExpand
The Conspicuous Absence of X-ray Emission from Carbon-Enriched Wolf-Rayet Stars.
Received idate?; Accepted idate? Abstract. The carbon-rich WC5star WR114 was not detected during a 15.9 ksec XMM-Newton observation, implying an upper limit to the X-ray luminosity of LX � 2.5 × 10Expand