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

Citation
G. Bertin et T. Toniazzo, COOLING FLOW MODELS OF THE X-RAY-EMISSION AND TEMPERATURE PROFILES FOR A SAMPLE OF ELLIPTIC GALAXIES, The Astrophysical journal, 451(1), 1995, pp. 111-124
Citations number
48
Categorie Soggetti
Astronomy & Astrophysics
Journal title
ISSN journal
0004637X
Volume
451
Issue
1
Year of publication
1995
Part
1
Pages
111 - 124
Database
ISI
SICI code
0004-637X(1995)451:1<111:CFMOTX>2.0.ZU;2-0
Abstract
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 emissi on profiles and temperatures for a set of bright elliptical galaxies i n Virgo and Fornax. Three free parameters are needed to specify the mo del: the external mass flux, the external pressure, and a dimensionles s factor, which regulates the mass deposition rate along the flow. Thr ee 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 betw een L(X)/L(B) and the iron abundance in the gas inside ellipticals is pointed out.