Photofluid instabilities of hot stellar envelopes

摘要

Beginning from a relatively simple set of dynamical equations for a fluid permeated by a radiative field strong enough to produce significant forces, we find the structure of plane-parallel equilibria and study their stability to small acoustic disturbances. In doing this, we neglect viscous effects and complications of nongrayness. We find that acoustic instabilities occur over a wide range of conditions below the Eddington limit. This result is in line with findings reported 20 years ago but it contradicts a more recent report of the absence of instabilities. We briefly attempt to identify the causes of the discrepancies and then close with allusions to the possible astrophysical interest of such instabilities. (C) 1999 Elsevier Science B.V. All rights reserved. [References: 17]