English

Breaking the sound barrier in recombination fronts

Astrophysics 2015-06-24 v1

Abstract

We exploit a generic instability in the integration of steady, sonic, near-isothermal flows to find the complete transition diagram for recombination fronts (for a model system of equations). The instability requires the integration of the flow equations for speeds between the isothermal and adiabatic sound speeds to be performed with particular care. As a result of this, the previous work of Newman & Axford on the structure of recombination fronts neglected an important class of solution, that of transonic fronts; our method is readily extensible to a more complete treatment of the ionization structure. Future papers will apply these results in models of the structure of ultracompact HII regions.

Keywords

Cite

@article{arxiv.astro-ph/9512116,
  title  = {Breaking the sound barrier in recombination fronts},
  author = {R. J. R. Williams and J. E. Dyson},
  journal= {arXiv preprint arXiv:astro-ph/9512116},
  year   = {2015}
}

Comments

Accepted for publication in MNRAS. LaTeX, 7 pages, 6 Postscript figures. Also available at http://axp2.ast.man.ac.uk:8000/Preprints.html