Spherical accretion in nearby weakly active galaxies
N. Copernicus Astronomical Center, Bartycka 18, 00-716, Warsaw, Poland e-mail: email@example.com
Accepted: 15 December 2005
We consider the sample of weakly active galaxies situated in the “Local Universe” with inferred accretion efficiencies from 10-2 to 10-7. We apply a model of spherically symmetrical Bondi accretion for given parameters (, , ,) taken from observation. We calculate spectra emitted by the gas accreting onto its central objects using a Monte Carlo method including synchrotron and bremsstrahlung photons as seed photons. We then compare our results with observed nuclear X-ray luminosities (0.3–10 keV) for the sample. A model is also tested for different external medium parameters ( and ) and different free parameters of the model. Our model is able to explain observed nuclear luminosities LX under an assumption that half of the compression energy is transferred directly to the electrons.
Key words: galaxies: nuclei / galaxies: active / galaxies: cooling flows
© ESO, 2006