A method for the study of accretion disk emission in cataclysmic variables. I. the model

Raúl E. Puebla, Marcos P. Diaz, D. John Hillier, Ivan - Hubeny

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

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.

Original languageEnglish (US)
Article number17
JournalAstrophysical Journal
Volume736
Issue number1
DOIs
StatePublished - Jul 20 2011

Fingerprint

cataclysmic variables
accretion disks
accretion
inclination
profiles
atmospheres
orbitals
atmosphere
ultraviolet emission
rings
velocity structure
resonance lines
ionization
temperature
signatures
method
continuums
trends
well
synthesis

Keywords

  • accretion, accretion disks
  • novae, cataclysmic variables
  • stars: mass-loss
  • ultraviolet: general

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

A method for the study of accretion disk emission in cataclysmic variables. I. the model. / Puebla, Raúl E.; Diaz, Marcos P.; John Hillier, D.; Hubeny, Ivan -.

In: Astrophysical Journal, Vol. 736, No. 1, 17, 20.07.2011.

Research output: Contribution to journalArticle

Puebla, Raúl E. ; Diaz, Marcos P. ; John Hillier, D. ; Hubeny, Ivan -. / A method for the study of accretion disk emission in cataclysmic variables. I. the model. In: Astrophysical Journal. 2011 ; Vol. 736, No. 1.
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