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J/A+A/508/309       Spectral atlas of HD 50138         (Borges Fernandes+, 2009)

The galactic unclassified B[e] star HD50138. I. A possible new shell-phase. Borges Fernandes M., Kraus M., Chesneau O., Domiciano de Souza A., de Araujo F.X., Stee P., Meilland A. <Astron. Astrophys. 508, 309 (2009)> =2009A&A...508..309B
ADC_Keywords: Stars, Be ; Spectroscopy ; Atlases Keywords: fundamental parameters - stars: winds, outflows - stars: individual: HD50138 Abstract: The observed spectral variation of HD50138 led different authors in the literature to classify it in a very large range of spectral types and luminosity classes (from B5 to A0 and III to Ia) and at different evolutionary stages, as either an HAeBe star or a classical Be. Based on new high-resolution optical spectroscopic data from 1999 and 2007, we perform a detailed spectral description, presenting the variations seen and discussing their possible origin. We tentatively suggest that a new shell phase could have taken place prior to our observations in 2007. We derive the interstellar extinction to HD50138 by taking into account the influences of the circumstellar matter in the form of dust and an ionized disk. We find a color excess value of E(B-V)=0.08mag. Based on photometric data from the literature and the new Hipparcos distance, we obtain a revised set of parameters for HD50138, suggesting that it is a B6-7 III-V star. A discussion about the different evolutionary scenarios is also provided. Description: In this table, it is described the lines identified, with their radial velocities and equivalent widths in the high-resolution FEROS spectra obtained in 1999 and 2007. FEROS is a bench-mounted Echelle spectrograph with fibers, which covers a sky area of 2" of diameter, with a wavelength coverage from 360nm to 920nm and a spectral resolution of R=55000 (in the region around 600nm). The spectrum of 1999 was obtained with an exposure time of 180 seconds and has a S/N ratio of approximately 80 in the 550nm region. In 2007, we were able to take two consecutive spectra of the star, both with 180 seconds of exposure time. Since these spectra do not show significant differences, we added them up for a better S/N ratio, which is around 250. Objects: ---------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------- 06 51 33.4 -06 57 59 HD 50138 = HIP 32923 ---------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 103 162 Spectral atlas of HD 50138
See also: J/A+AS/128/475 : Spectroscopy of MWC 158 = HD 50138 (Jaschek+ 1998) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 6 F6.1 0.1nm lam(99) ? Observed Wavelength (1999) 8- 12 F5.1 km/s Vel(99) ? Heliocentric Radial Velocity (1999) (1) 14- 18 F5.2 0.1nm Wbe(99) ? Equivalent Width (Blue Emission Comp. 1999) 20- 24 F5.2 0.1nm Wab(99) ? Equivalent Width (Absorption Component 1999) 26- 30 F5.2 0.1nm Wre(99) ? Equivalent Width (Red Emission Comp. 1999) 32- 37 F6.1 0.1nm lam(07) ? Observed Wavelength (2007) 39- 43 F5.1 km/s Vel(07) ? Heliocentric Radial Velocity (2007) (1) 45- 49 F5.2 0.1nm Wbe(07) ? Equivalent Width (Blue Emission Comp. 2007) 51- 55 F5.2 0.1nm Wab(07) ? Equivalent Width (Absorption Component 2007) 57- 61 F5.2 0.1nm Wre(07) ? Equivalent Width (Red Emission Comp. 2007) 63-103 A41 --- Com Identification of the lines (2)
Note (1): The heliocentric radial velocities were measured related to the center of the line (considering the wings of the line) and the rest wavelength. Note (2): For the line identification, we provide not only the name of the ion, but also the multiplet and the rest wavelength. For some lines there are more than one possible classification, however the radial velocity was derived assuming the first identification cited. There, "Uid" means that the line is unidentified.
Acknowledgements: Marcelo Borges Fernandes, marcelo.borges(at)obs-azur.fr
(End) M. Borges Fernandes [Obs. Cote d'Azur], Patricia Vannier [CDS] 15-Sep-2009
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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