Search Publications
Wolf-Rayet stars in the Small Magellanic Cloud. I. Analysis of the single WN stars
Sander, A.; Hamann, W. -R.; Shenar, T. +3 more
Context. Wolf-Rayet (WR) stars have a severe impact on their environments owing to their strong ionizing radiation fields and powerful stellar winds. Since these winds are considered to be driven by radiation pressure, it is theoretically expected that the degree of the wind mass-loss depends on the initial metallicity of WR stars.
Aims: Foll…
Spectral and spatial imaging of the Be+sdO binary ϕ Persei
Berio, P.; Meilland, A.; Millour, F. +25 more
Aims: The rapidly rotating Be star
Non-conservative evolution in Algols: where is the matter?
Baes, M.; Jorissen, A.; Siess, L. +3 more
Context. There is indirect evidence of non-conservative evolutions in Algols. However, the systemic mass-loss rate is poorly constrained by observations and generally set as a free parameter in binary-star evolution simulations. Moreover, systemic mass loss may lead to observational signatures that still need to be found.
Aims: Within the "ho…
Multitechnique testing of the viscous decretion disk model. I. The stable and tenuous disk of the late-type Be star β CMi
Carciofi, A. C.; Rivinius, Th.; Štefl, S. +10 more
Context. The viscous decretion disk (VDD) model is able to explain most of the currently observable properties of the circumstellar disks of Be stars. However, more stringent tests, focusing on reproducing multitechnique observations of individual targets via physical modeling, are needed to study the predictions of the VDD model under specific ci…
A spectroscopic investigation of the O-type star population in four Cygnus OB associations. II. Determination of the fundamental parameters
Rauw, G.; De Becker, M.; Mahy, L. +2 more
Aims: Having established the binary status of nineteen O-type stars located in four Cygnus OB associations, we now determine their fundamental parameters to constrain their properties and their evolutionary status. We also investigate their surface nitrogen abundances, which we compare with other results from the literature obtained for galac…
Visual and ultraviolet flux variability of the bright CP star θ Aurigae
Krtička, J.; Lüftinger, T.; Mikulášek, Z. +1 more
Context. Chemically peculiar stars of the upper part of the main sequence show periodical variability in line intensities and continua, modulated by the stellar rotation, which is attributed to the existence of chemical spots on the surface of these stars. The flux variability is caused by the changing redistribution rate of the radiative flux pre…
The Mg i line: a new probe of the atmospheres of evaporating exoplanets
Lecavelier des Etangs, A.; Bourrier, V.; Vidal-Madjar, A.
Transit observations of HD 209458b in the UV revealed signatures of neutral magnesium escaping the planet's upper atmosphere. The absorption detected in the Mg i line provides unprecedented information on the physical conditions at the altitude where the atmospheric blow-off takes place. Here we use a 3D model of atmospheric escape to estimate the…
The fundamental parameters of the Ap star 78 Virginis. Could 78 Vir be a rapidly oscillating Ap star?
Meilland, A.; Sturmann, J.; Sturmann, L. +11 more
Context. Determining the effective temperature of Ap stars, including the roAp stellar pulsators, is a difficult task owing to their strong magnetic field and their related spotted surfaces. It is, however, an important step towards constraining models of their complex atmosphere and testing proposed pulsation excitation mechanisms.
Aims: Usi…