Neutral material around the B[e] supergiant star LHA115-S 65 An outflowing disk or a detached Keplerian rotating disk?

0354843 - ASÚ 2011 RIV FR eng J - Journal Article
Kraus, Michaela - Borges Fernandes, M. - de Araújo, F. X.
Neutral material around the B[e] supergiant star LHA115-S 65 An outflowing disk or a detached Keplerian rotating disk?
Astronomy & Astrophysics. July, č. 517 (2010), A30/1-A30/13. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA AV ČR KJB300030701
Institutional research plan: CEZ:AV0Z10030501
Keywords : supergiants * circumstellar matter * outflows
Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
Impact factor: 4.410, year: 2010

The B[e] supergiant LHA 115-S 65 (in short: S 65) in the Small Magellanic Cloud is one of the two most rapidly rotating B[e] stars known. Its almost edge-on orientation allows a detailed kinematical study of its optically thin forbidden emission lines. With a focus on the rather strong [Oi] lines, we intend to test the two plausible disk scenarios: the outflowing and the Keplerian rotating disk. Both disk scenarios deliver reasonably good fits to the line luminosities and profiles of the [Oi] lines. Nevertheless, the Keplerian disk model seems to be the more realistic one, because it also agrees with the kinematics derived from the large number of additional lines in the spectrum. As additional support for the presence of a high-density, gaseous disk, the spectrum shows two very intense and clearly double-peaked [Caii] lines. We discuss a possible disk-formation mechanism, and similarities between S 65 and the group of Luminous Blue Variables.
Permanent Link: http://hdl.handle.net/11104/0193756