Be discs in binary systems - I. Coplanar orbits

Autor(es)

Panoglou, Despina ; Carciofi, Alex C. ; Vieira, Rodrigo G. ; Cyr, Isabelle H. ; Jones, Carol E. ; Okazaki, Atsuo T. ; Rivinius, Thomas

• Tipo de documento: Artigo Científico
• Fonte: Monthly Notices of the Royal Astronomical Society; v. 461, n. 3, p. 2616-2629, SEP 21 2016.
• Citações Web of Science: 19

Resumo

Be stars are surrounded by outflowing circumstellar matter structured in the form of decretion discs. They are often members of binary systems, where it is expected that the decretion disc interacts both radiatively and gravitationally with the companion. In this work we study how various orbital (period, mass ratio and eccentricity) and disc (viscosity) parameters affect the disc structure in coplanar binaries. The main effects of the secondary on the disc are its truncation and the accumulation of material inwards of truncation. We find two limiting cases with respect to the effects of eccentricity: in circular or nearly circular prograde orbits, the disc maintains a rotating, constant in shape, configuration, which is locked to the orbital phase. The disc structure appears smaller in size, more elongated and more massive for small viscosity parameter, small orbital separation and/or high mass ratio. In highly eccentric orbits, the effects are more complex, with the disc structure strongly dependent on the orbital phase. We also studied the effects of binarity in the disc continuum emission. Since the infrared and radio SED are sensitive to the disc size and density slope, the truncation and matter accumulation result in considerable modifications in the emergent spectrum. We conclude that binarity can serve as an explanation for the variability exhibited in observations of Be stars, and that our model can be used to detect invisible companions. (AU)

• Processo FAPESP: 13/16801-2 - Modelagem da formação e evolução de discos estelares gasosos de acreção e decreção
• Beneficiário: Despina Panoglou
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 15/17967-7 - Discos de decréscimo viscoso: teoria e observações
• Beneficiário: Alex Cavaliéri Carciofi
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 09/54006-4 - Um cluster de computadores para o Departamento de Astronomia do IAG-USP e para o Núcleo de Astrofísica da UNICSUL
• Beneficiário: Elisabete Maria de Gouveia Dal Pino
• Linha de fomento: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 12/20364-4 - Além da sobrevivência da poeira: as regiões internas de discos protoplanetários
• Beneficiário: Rodrigo Georgetti Vieira
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado