Comoving frame models of hot star winds - I. Test of the Sobolev approximation in the case of pure line transitions

  title={Comoving frame models of hot star winds - I. Test of the Sobolev approximation in the case of pure line transitions},
  author={Jiř{\'i} Krti{\vc}ka and Jǐŕı Kub{\'a}t},
  journal={Astronomy and Astrophysics},
We provide hot star wind models with radiative force calculated using the solution of comoving frame (CMF) radiative transfer equation. The wind models are calculated for the first stars, O stars, and the central stars of planetary nebulae. We show that without line overlaps and with solely thermal line broadening the pure Sobolev approximation provides a reliable estimate of the radiative force even close to the wind sonic point. Consequently, models with the Sobolev line force provide good… Expand

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