| Full text | |
| Author(s): Show less - |
Rubio, A. C.
;
Carciofi, A. C.
;
Ticiani, P.
;
Mota, B. C.
;
Vieira, R. G.
;
Faes, D. M.
;
Genaro, M.
;
de Amorim, T. H.
;
Klement, R.
;
Araya, I
;
Arcos, C.
;
Cure, M.
;
Domiciano de Souza, A.
;
Georgy, C.
;
Jones, C. E.
;
Suffak, M. W.
;
Silva, A. C. F.
Total Authors: 17
|
| Document type: | Journal article |
| Source: | Monthly Notices of the Royal Astronomical Society; v. 526, n. 2, p. 30-pg., 2023-10-10. |
| Abstract | |
Classical B emission (Be) stars are fast rotating, near-main-sequence B-type stars. The rotation and the presence of circumstellar discs profoundly modify the observables of active Be stars. Our goal is to infer stellar and disc parameters, as well as distance and interstellar extinction, using the currently most favoured physical models for these objects. We present BEATLAS, a grid of 61600 non-local thermodynamic equilibrium radiative transfer models for Be stars, calculated with the HDUST code. The grid was coupled with a Monte Carlo Markov chain (MCMC) code to sample the posterior distribution. We test our method on two well-studied Be stars, alpha Eri and beta CMi, using photometric, polarimetric, and spectroscopic data as input to the code. We recover literature determinations for most of the parameters of the targets, in particular the mass and age of alpha Eri, the disc parameters of beta CMi, and their distances and inclinations. The main discrepancy is that we estimate lower rotational rates than previous works. We confirm previously detected signs of disc truncation in beta CMi and note that its inner disc seems to have a flatter density slope than its outer disc. The correlations between the parameters are complex, further indicating that exploring the entire parameter space simultaneously is a more robust approach, statistically. The combination of BEATLAS and Bayesian-MCMC techniques proves successful, and a powerful new tool for the field: The fundamental parameters of any Be star can now be estimated in a matter of hours or days. (AU) | |
| FAPESP's process: | 21/01891-2 - 3-D hydrodynamic simulations coupled with radiative transfer |
| Grantee: | Tajan Henrique de Amorim |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |
| FAPESP's process: | 17/08001-7 - Searching for invisible binary companions of Be stars |
| Grantee: | Amanda Caveagna Rubio |
| Support Opportunities: | Scholarships in Brazil - Master |
| FAPESP's process: | 18/04055-8 - High precision spectroscopy: from the first stars to planets |
| Grantee: | Jorge Luis Melendez Moreno |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 09/54006-4 - A computer cluster for the Astronomy Department of the University of São Paulo Institute of Astronomy, Geophysics and Atmospheric Sciences and for the Cruzeiro do Sul University Astrophysics Center |
| Grantee: | Elisabete Maria de Gouveia Dal Pino |
| Support Opportunities: | Multi-user Equipment Program |
| FAPESP's process: | 19/13354-1 - Decretion disks and outflows around fast-spinning stars |
| Grantee: | Alex Cavaliéri Carciofi |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 18/26380-8 - Dust modeling in red supergiants Using Bayesian inference |
| Grantee: | Tajan Henrique de Amorim |
| Support Opportunities: | Scholarships in Brazil - Scientific Initiation |
| FAPESP's process: | 18/05326-5 - Bayesian inference of fundamental Be Star parameters by means of spectroscopic observations |
| Grantee: | Matheus Genaro Dantas Xavier |
| Support Opportunities: | Scholarships in Brazil - Scientific Initiation |