Article (Scientific journals)
The puzzling Luminous Blue Variable-like object HD 5980 in the Small Magellanic Cloud.
Heydari-Malayeri, M.; Rauw, Grégor; Esslinger, O. et al.
1997In Astronomy and Astrophysics, 322, p. 554-564
Peer Reviewed verified by ORBi
 

Files


Full Text
1997A+A...322..554H.pdf
Publisher postprint (306.63 kB)
Request a copy

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
STARS: WOLF-RAYET; STARS: INDIVIDUAL: HD 5980; BINARIES: ECLIPSING; STARS: MASS-LOSS; CIRCUMSTELLAR MATTER; MAGELLANIC CLOUDS
Abstract :
[en] We have observed the exceptional SMC star HD 5980 during several runs from 1989 to 1995 at ESO La Silla. CASPEC at the 3.6m telescope and EMMI in echelle and long slit modes at NTT were used for spectroscopy. Sub-arcsecond images were obtained using SUSI at NTT and also an adaptive optics system at the 3.6m telescope. In all our spectra taken before 1994 September HD 5980 shows a spectral type of WN6. The 1994 September spectra were taken shortly after the maximum of the visual light-curve of the LBV-like phenomenon (Bateson & Jones, 1993PVSS...19...50B) and about one month before the observations of Barba et al. (1995ApJ...446L..23B). Near maximum visual brightness, HD 5980 displays a WN11-like spectrum with the HeI lines and the Balmer lines Hdelta and Hgamma showing well-developed PCyg profiles. The sub-arcsecond images (0.17" FWHM), through the near infrared bands J, H, and K, obtained in 1993 and 1996, show no stellar components down to 6.7 mag fainter than HD 5980 in K at a separation of 1.0" and the 3sigma level. For a separation of 0.3" this upper bound is 4.1mag fainter than HD 5980. The observed behavior of this object raises serious problems for our comprehension of the LBV phenomenon in the conventional scenarios of massive star evolution. The present observations cover a crucial period in the evolution of HD 5980 and will therefore be helpful for better understanding this peculiar object especially during its outburst as well as the evolution of W-R stars in general.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Heydari-Malayeri, M.
Rauw, Grégor  ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Groupe d'astrophysique des hautes énergies (GAPHE) - Sciences spatiales
Esslinger, O.
Beuzit, J.-L.
Language :
English
Title :
The puzzling Luminous Blue Variable-like object HD 5980 in the Small Magellanic Cloud.
Publication date :
01 June 1997
Journal title :
Astronomy and Astrophysics
ISSN :
0004-6361
eISSN :
1432-0746
Publisher :
EDP Sciences, Les Ulis, France
Volume :
322
Pages :
554-564
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 02 July 2009

Statistics


Number of views
150 (0 by ULiège)
Number of downloads
0 (0 by ULiège)

Scopus citations®
 
17
Scopus citations®
without self-citations
15

Bibliography


Similar publications



Contact ORBi