A METHOD FOR THE STUDY OF ACCRETION DISK EMISSION IN CATACLYSMIC VARIABLES. I. THE MODEL

Autor(es)

Puebla, Raul E. ^[1] ; Diaz, Marcos P. ^[1] ; Hillier, D. John ^[2] ; Hubeny, Ivan ^[3]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo - Brazil

^[2] Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA - USA

^[3] Univ Arizona, Steward Observ, Dept Astron, Tucson, AZ 85721 - USA

• Tipo de documento: Artigo Científico
• Fonte: ASTROPHYSICAL JOURNAL; v. 736, n. 1 JUL 20 2011.
• Citações Web of Science: 5

Resumo

We have developed a spectrum synthesis method for modeling the ultraviolet (UV) emission from the accretion disk from cataclysmic variables (CVs). The disk is separated into concentric rings, with an internal structure from the Wade \& Hubeny disk-atmosphere models. For each ring, a wind atmosphere is calculated in the comoving frame with a vertical velocity structure obtained from a solution of the Euler equation. Using simple assumptions, regarding rotation and the wind streamlines, these one-dimensional models are combined into a single 2.5-dimensional model for which we compute synthetic spectra. We find that the resulting line and continuum behavior as a function of the orbital inclination is consistent with the observations, and verify that the accretion rate affects the wind temperature, leading to corresponding trends in the intensity of UV lines. In general, we also find that the primary mass has a strong effect on the P Cygni absorption profiles, the synthetic emission line profiles are strongly sensitive to the wind temperature structure, and an increase in the mass-loss rate enhances the resonance line intensities. Synthetic spectra were compared with UV data for two high orbital inclination nova-like CVs-RW Tri and V347 Pup. We needed to include disk regions with arbitrary enhanced mass loss to reproduce reasonably well widths and line profiles. This fact and a lack of flux in some high ionization lines may be the signature of the presence of density-enhanced regions in the wind, or alternatively, may result from inadequacies in some of our simplifying assumptions. (AU)

• Processo FAPESP: 11/08654-4 - Um método para o estudo da emissão de discos de acresção em variáveis cataclísmicas
• Beneficiário: Marcos Perez Diaz
• Modalidade de apoio: Auxílio à Pesquisa - Publicações científicas - Artigo
• Processo FAPESP: 05/04128-5 - Sintese espectral detalhada de discos de acrescao.
• Beneficiário: Raúl Eduardo Puebla Puebla
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 10/16010-7 - Teste observacional da síntese espectral de discos de acresção com vento.
• Beneficiário: Raúl Eduardo Puebla Puebla
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado