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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

DYNAMICAL EVOLUTION OF VISCOUS DISKS AROUND BE STARS. II. POLARIMETRY

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Author(s):
Haubois, X. [1, 2, 3] ; Mota, B. C. [1] ; Carciofi, A. C. [1] ; Draper, Z. H. [4, 5] ; Wisniewski, J. P. [6] ; Bednarski, D. [1] ; Rivinius, Th [7]
Total Authors: 7
Affiliation:
[1] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo - Brazil
[2] Univ Paris Diderot, UPMC, CNRS UMR 8109, Observ Paris, LESIA, F-92195 Meudon - France
[3] Univ Sydney, Sch Phys, Sydney Inst Astron, Sydney, NSW 2006 - Australia
[4] Univ Victoria, Dept Phys & Astron, Victoria, BC V8P 5C2 - Canada
[5] Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC V9E 2E7 - Canada
[6] Univ Oklahoma, HL Dodge Dept Phys & Astron, Norman, OK 73019 - USA
[7] European Org Astron Res Southern Hemisphere, Santiago 19 - Chile
Total Affiliations: 7
Document type: Journal article
Source: ASTROPHYSICAL JOURNAL; v. 785, n. 1 APR 10 2014.
Web of Science Citations: 17
Abstract

Be stars exhibit variability for a great number of observables. Putting the pieces of the disk dynamics together is not an easy task and requires arduous modeling before achieving a good fit to the observational data. In order to guide the modeling process and make it more efficient, it is very instructive to investigate reference dynamical cases. This paper focuses on continuum polarimetric quantities and is the second of a series that aims to demonstrate the capacity of deriving the dynamical history and fundamental parameters of a classical Be star through follow-up of various observables. After a detailed study of the different opacities at play in the formation of polarized spectra, we investigate predictions of polarimetric observables in the continuum for different dynamical scenarios. Our models are based on a coupling of a hydrodynamic viscous decretion simulations in a disk and a three-dimensional non-LTE radiative transfer code. Through introduction of the polarization color diagram (PCD), we show that certain combinations of polarimetric observables exhibit features that are characteristic of a mass-loss history. This diagram also enables estimates of fundamental parameters such as the inclination angle, disk density scale, and the a viscous diffusion parameter. We present the PCD as a powerful diagnosis tool to track the dynamical phases of a Be star, such as disk build-up, dissipation, periodic, and episodic outbursts. Finally, we confront our models with observations of four Be stars that exhibited long-term polarimetric activity. (AU)

FAPESP's process: 10/19029-0 - 3D radiative transfer models: bridging theory and observations
Grantee:Alex Cavaliéri Carciofi
Support type: Regular Research Grants
FAPESP's process: 09/07477-1 - Probing atmospheres and circumstellar environments of Be stars and evolved low mass stars with interferometry and polarimetry
Grantee:Xavier Marie Alain Haubois
Support type: Scholarships in Brazil - Post-Doctorate
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 type: Multi-user Equipment Program