The circumstellar environments of B[e] Supergiants

0485384 - ASÚ 2018 GB eng C - Conference Paper (international conference)
Maravelias, Grigorios - Kraus, Michaela - Cidale, L.S. - Arias, M.L. - Aret, Anna - Borges Fernandes, M.
The circumstellar environments of B[e] Supergiants.
The Lives and Death-Throes of Massive Star. Cambridge: Cambridge University Press, 2017, s. 421-421. Proceedings of the International Astronomical Union, IAU S329. ISBN 9781107170063. ISSN 1743-9213.
[Symposium of the International Astronomical Union /329./. Auckland (NZ), 28.11.2016-02.12.2016]
R&D Projects: GA ČR(CZ) GA14-21373S
Institutional support: RVO:67985815
Keywords : stars * circumstellar matter * emission-line
OECD category: Astronomy (including astrophysics,space science)

The evolution of massive stars encompasses short-lived transition phases in which mass-loss is more enhanced and usually eruptive. A complex environment, combining atomic, molecular and dust regions, is formed around these stars. In particular, the circumstellar environment of B[e] Supergiants is not well understood. To address that, we have initiated a campaign to investigate their environments for a sample of Galactic and Magellanic Cloud sources. Using high-resolution optical and near-infrared spectra (MPG-ESO/FEROS, GEMINI/Phoenix and VLT/CRIRES, respectively), we examine a set of emission features ([OI], [CaII], CO bandheads) to trace the physical conditions and kinematics in their formation regions. We find that the B[e] Supergiants are surrounded by a series of rings of different temperatures and densities, a probable result of previous mass-loss events. In many cases the CO forms very close to the star, while we notice also an alternate mixing of densities and temperatures (which give rise to the different emission features) along the equatorial plane.
Permanent Link: http://hdl.handle.net/11104/0280425