The galactic unclassified B[e] star HD 50138 - I. A possible new shell phase

@article{Fernandes2009TheGU,
  title={The galactic unclassified B[e] star HD 50138 - I. A possible new shell phase},
  author={M. Fernandes and M. Kraus and O. Chesneau and A. D. D. Souza and F. X. Ara{\'u}jo and P. Stee and Anthony Meilland Fizeau and France. and A. Ondrejov and Czech Repubic and O. Nacional and Brazil. and Mpifr and H Germany},
  journal={Astronomy and Astrophysics},
  year={2009},
  volume={508},
  pages={309-320}
}
Context. The observed spectral variation of HD 50138 has led different authors to classify it in a very wide range of spectral types and luminosity classes (from B5 to A0 and III to Ia) and at different evolutionary stages as either HAeBe star or classical Be. Aims. Based on new high-resolution optical spectroscopic data from 1999 and 2007 associated to a photometric analysis, the aim of this work is to provide a deep spectroscopic description and a new set of parameters for this unclassified… Expand
The Galactic unclassified B[e] star HD 50138 - III. The short-term line profile variability of its photospheric lines
Context. HD 50138 presents the B[e] phenomenon, but its nature is not clear yet. This star is known to present spectral variations, which have been associated with outbursts and shell phases. Aims.Expand
The galactic unclassified B(e) star HD 50138 ??? II. Interferometric constraints on the close circumstellar environment
Context. HD 50138 is a southern star that presents the B[e] phenomenon, but its evolutionary stage is still not well known. This object presents spectral variability, which can be explained byExpand
Dust evolution in the circumstellar disc of the unclassified B[e] star HD 50138
We studied the disc of the unclassified B[e] star HD 50138, in order to explore its structure, and to find indications for the evolutionary status of this system, whether it is a young Herbig Be or aExpand
A resolved, au-scale gas disk around the B[e] star HD 50138
HD 50138 is a B[e] star surrounded by a large amount of circumstellar gas and dust. Its spectrum shows characteristics which may indicate either a pre- or a post-main-sequence system. Mapping theExpand
The circumstellar environment of HD50138 revealed by VLTI/AMBER at high angular resolution
HD50138 is a Herbig B[e] star with a circumstellar disc detected at IR and mm wavelength. Its brightness makes it a good candidate for NIR interferometry observations. We aim to resolve, spatiallyExpand
The study of unclassified B[e] stars and candidates in the Galaxy and Magellanic Clouds†
We investigated 12 unclassified B[e] stars or candidates, 8 from the Galaxy, 2 from the Large Magellanic Cloud (LMC) and 2 from the Small Magellanic Cloud (SMC). Based on the analysis ofExpand
Time-dependent spectral-feature variations of stars displaying the B[e] phenomenon - III. HD 50138
Context. B[e] stars are anomalous objects around which extended circumstellar matter is present. The observed properties of the central star are significantly affected by the surrounding material.Expand
An ultraviolet study of B[e] stars: evidence for pulsations, luminous blue variable type variations and processes in envelopes
Stars that exhibit a B[e] phenomenon comprise a very diverse group of objects in a different evolutionary status. These objects show common spectral characteristics, including the presence of BalmerExpand
A disk asymmetry in motion around the B[e] star MWC158
MWC158 is a star with the B[e] phenomenon that shows strong spectrophotometric variability (in lines and in UV and visible continuum) attributed to phases of shell ejection. The evolutionary stage ofExpand
On the Nature of the Herbig B[e] Star Binary System V921?Scorpii: Discovery of a Close Companion and Relation to the Large-scale Bipolar Nebula
Belonging to the group of B[e] stars, V921 Scorpii is associated with a strong infrared excess and permitted and forbidden line emission, indicating the presence of low- and high-densityExpand
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