The VLT-FLAMES Tarantula Survey:V. the peculiar B[e]-like supergiant, VFTS698, in 30 Doradus


Autoria(s): Dunstall, P. R.; Fraser, M.; Clark, J. S.; Crowther, P. A.; Dufton, P. L.; Evans, C. J.; Lennon, D. J.; Soszyński, I.; Taylor, W. D.; Vink, J. S.
Data(s)

2012

Resumo

<p>Aims. We present an analysis of a peculiar supergiant B-type star (VFTS698/Melnick 2/Parker 1797) in the 30 Doradus region of the Large Magellanic Cloud which exhibits characteristics similar to the broad class of B[e] stars. Methods. We analyse optical spectra from the VLT-FLAMES survey, together with archival optical and infrared photometry and X-ray imaging to characterise the system. Results. We find radial velocity variations of around 400 km s <sup>-1</sup> in the high excitation Si iv, N iii and He ii spectra, and photometric variability of ∼0.6 mag with a period of 12.7 d. In addition, we detect long-term photometric variations of ∼0.25 mag, which may be due to a longer-term variability with a period of ∼400 d. Conclusions. We conclude that VFTS698 is likely an interacting binary comprising an early B-type star secondary orbiting a veiled, more massive companion. Spectral evidence suggests a mid-to-late B-type primary, but this may originate from an optically-thick accretion disc directly surrounding the primary. © 2012 ESO.</p>

Identificador

http://pure.qub.ac.uk/portal/en/publications/the-vltflames-tarantula-survey(2349ab53-b7e3-4d66-9d2e-36ee844a5636).html

http://dx.doi.org/10.1051/0004-6361/201218872

http://www.scopus.com/inward/record.url?scp=84861884374&partnerID=8YFLogxK

Idioma(s)

eng

Direitos

info:eu-repo/semantics/restrictedAccess

Fonte

Dunstall , P R , Fraser , M , Clark , J S , Crowther , P A , Dufton , P L , Evans , C J , Lennon , D J , Soszyński , I , Taylor , W D & Vink , J S 2012 , ' The VLT-FLAMES Tarantula Survey : V. the peculiar B[e]-like supergiant, VFTS698, in 30 Doradus ' Astronomy and Astrophysics , vol 542 , A50 . DOI: 10.1051/0004-6361/201218872

Palavras-Chave #Be #Binaries: spectroscopic #Stars: early-type #Stars: emission-line #Stars: peculiar #Stars: variables: general #/dk/atira/pure/subjectarea/asjc/3100/3103 #Astronomy and Astrophysics #/dk/atira/pure/subjectarea/asjc/1900/1912 #Space and Planetary Science
Tipo

article