Suchergebnisse

Considering the physical structure of the stellar envelope a new solution of the equation of equilibrium is obtained, which is free of approximations. In determination of the mass in the stellar envelope Chandrasekhar's solution requires further approximation in the process of integration, whereas new solution obtained here requires no approximation. In the particular case of vanishing radiation pressure results are in full agreement with those of Chandrasekhar. The application of result in a stellar model is also discussed and neff is calculated. The expression for neff assumes a simple form and its typical values are the same as obtained by Chandrasekhar.

The propagation of sonic discontinuities of arbitrary shape has been studied in a 3-dimensional gas flow with vibrational relaxation. The law of propagation is determined and the problem of growth and decay of waves has been solved. The effects of the wave geometry and that of vibrational relaxation on the global behaviour of the wave amplitude have been studied. It is found that the vibrational relaxation has a stabilizing effect on the wave in the sense that either it disallows or delays the shock formation. The two cases of diverging and converging waves have been discussed separately.