COOLING FLOW MODELS OF THE X-RAY-EMISSION AND TEMPERATURE PROFILES FOR A SAMPLE OF ELLIPTIC GALAXIES

A simple spherically symmetric, steady state, cooling flow description with gas loss (following Sarazin and Ashe 1989), within galaxy models constrained by radially extended stellar dynamical data, is shown to provide generally reasonable fits to the existing data on X-ray emission profiles and temperatures for a set of bright elliptical galaxies in Virgo and Fornax. Three free parameters are needed to specify the model: the external mass flux, the external pressure, and a dimensionless factor, which regulates the mass deposition rate along the flow. Three different assumptions on the supernova rate have been considered. A moderate value for the supernova rate in elliptical galaxies is found to be preferred. Confining pressures of p(ext) similar to 4-15 x 10(3) K cm(-3) and significant accretion rates of external material, up to 4 M. yr(-1), are suggested by our models. A possible correlation between L(X)/L(B) and the iron abundance in the gas inside ellipticals is pointed out.