The structure of radiative shock waves

IV. Effects of electron thermal conduction

¹ Institute for Astronomy of the Russian Academy of Sciences, Pyatnitskaya 48, 109017 Moscow, Russia
² Observatoire de Haute-Provence – CNRS, 04870 Saint-Michel l'Observatoire, France

Corresponding author: D. Gillet, gillet@obs-hp.fr

Received: 12 September 2001
Accepted: 11 June 2002

Abstract

We consider the structure of steady–state radiative shock waves propagating in partially ionized hydrogen gas with density and temperature . The radiative shock wave models with electron thermal conduction in the vicinity of the viscous jump are compared with pure radiative models. The threshold shock wave velocity above which effects of electron thermal conduction become perceptible is found to be and corresponds to the upstream Mach numbers from at to at . In shocks with efficient electron heat conduction more than a half of the hydrogen atoms are ionized in the radiative precursor, whereas behind the viscous jump the hydrogen gas undergoes the full ionization. The existence of the electron heat conduction precursor leads to the enhancement of the Lyman continuum flux trapped in the surroundings of the discontinuous jump. As a result, the partially ionized hydrogen gas of the radiative precursor undergoes an additional ionization (), whereas the total radiave flux emerging from the shock wave increases by for .