Accretion disk winds in dwarf novae


Ozkan M. T. , Ak T. , Gülseçen H. , Esenoglu H. H. , Saygac A. T.

Conference of the NATO-Advanced-Study-Institute on Variable Stars as Essential Astrophysical Tools, CESME, Türkiye, 31 Ağustos - 10 Eylül 1998, cilt.544, ss.751-757 identifier

  • Cilt numarası: 544
  • Basıldığı Şehir: CESME
  • Basıldığı Ülke: Türkiye
  • Sayfa Sayısı: ss.751-757

Özet

It is well known that the International Ultraviolet Explorer observations of high-excitation P Cygni profiles of C IV and S IV lines provide direct evidence for winds in cataclysmic variables which reach speeds of similar to 5000 km s(-1). We present in this paper our analysis of P Cygni profile for C IV line in seven dwarf novae based on 195 low-resolution IUE spectra. This work aims to do two things: i) to examine them in terms of wind properties, and ii) to seek time dependence of the lines indicating departure from axial symmetry in the outflow and/or disk and changes in the wind ionisation and/or mass loss rate. We infer the optical depth of C IV, the column density and the number density of absorbing and scattering ions in the region where the wind ionized.