Search Publications
Quantitative studies of the optical and UV spectra of Galactic early B supergiants. I. Fundamental parameters
Massa, D.; Prinja, R. K.; Searle, S. C. +1 more
Aims: We undertake an optical and ultraviolet spectroscopic analysis of a sample of 20 Galactic B0-B5 supergiants of luminosity classes Ia, Ib, Iab, and II. Fundamental stellar parameters are obtained from optical diagnostics and a critical comparison of the model predictions to observed UV spectral features is made.
Methods: Fundamental param…
Disks around CQ Tauri and MWC 758: dense PDR or gas dispersal?
Chapillon, E.; Guilloteau, S.; Dutrey, A. +1 more
Context: The overall properties of disks surrounding intermediate PMS stars (HAe) are not yet well constrained by current observations. The disk inclination, which significantly affects spectral energy distribution modeling, is often unknown.
Aims: We attempted to resolve the disks around CQ Tau and MWC 758 to provide accurate constraints on t…
High-resolution optical spectroscopy of Plaskett's star
Martins, F.; Gosset, E.; Rauw, G. +3 more
Context: Plaskett's star (
Quantitative spectroscopy of Deneb
Przybilla, N.; Schiller, F.
Context: Quantitative spectroscopy of luminous BA-type supergiants offers a high potential for modern astrophysics. Detailed studies allow the evolution of massive stars, galactochemical evolution, and the cosmic distance scale to be constrained observationally.
Aims: A detailed and comprehensive understanding of the atmospheres of BA-type sup…
The qWR star HD 45166. II. Fundamental stellar parameters and evidence of a latitude-dependent wind
Oliveira, A. S.; Steiner, J. E.; Groh, J. H.
Context: The enigmatic object HD 45166 is a qWR star in a binary system with an orbital period of 1.596 day, and presents a rich emission-line spectrum in addition to absorption lines from the companion star (B7 V). As the system inclination is very small (i=0.77° ± 0.09°), HD 45166 is an ideal laboratory for wind-structure studies.
Aims: The …
Magnetic field measurements and wind-line variability of OB-type stars
Rygl, K. L. J.; Neiner, C.; Wiersema, K. +8 more
Context: The first magnetic fields in O- and B-type stars that do not belong to the Bp-star class, have been discovered. The cyclic UV wind-line variability, which has been observed in a significant fraction of early-type stars, is likely to be related to such magnetic fields.
Aims: We attempt to improve our understanding of massive-star magne…
The secrets of T Pyxidis. II. A recurrent nova that will not become a SN Ia
Selvelli, P.; González-Riestra, R.; Gilmozzi, R. +1 more
Aims: We compare the observed and theoretical parameters for the quiescent and outburst phases of the recurring nova T Pyx.
Methods: IUE data were used to derive the disk luminosity and the mass accretion rate, and to exclude the presence of quasi-steady burning at the WD surface. XMM-NEWTON data were used to verify this conclusion.
Result…
Mg II h+k emission lines as stellar activity indicators of main sequence F-K stars
Buccino, A. P.; Mauas, P. J. D.
Context: The largest dataset of stellar activity measurements available at present is the one obtained at the Mount Wilson Observatory, where high-precision Ca II H+K fluxes have been measured from 1966 for about 2200 stars. Since the Mg II h and k lines at λ2800 Å are formed in a similar way to the Ca II H+K emission lines, they are also good ind…
Molecular hydrogen in the circumstellar environments of Herbig Ae/Be stars probed by FUSE
Deleuil, M.; Bouret, J. -C.; Roberge, A. +7 more
Context: Molecular hydrogen (H2) gas is the most abundant molecule in the circumstellar (CS) environments of young stars. It is thus a key element in our understanding of the evolution of pre-main sequence stars and their environments towards the main sequence.
Aims: At the present time, little is known about the gas as compared to the dust in…
Abundances of planetary nebula NGC 2392
Pottasch, S. R.; Bernard-Salas, J.; Roellig, T. L.
The spectra of the planetary nebula