Quasars: the characteristic spectrum and the induced radiative heating

By S. Sazonov, Jeremiah P. Ostriker, R. Sunyaev. 2003

185 citations recorded by the source corpus.

Using information on the cosmic X-ray background and the cumulative light of active galactic nuclei (AGN) at infrared wavelengths, the estimated local mass density of galactic massive black holes (MBHs) and published AGN composite spectra in the optical, UV and X-ray, we compute the characteristic angular-integrated, broad-band spectral energy distribution of the average quasar in the universe. We demonstrate that the radiation from such sources can photoionize and Compton heat the plasma surrounding them up to an equilibrium Compton temperature (T C ) of 2 x 10 7 K. It is shown that circumnuclear obscuration cannot significantly affect the net gas Compton heating and cooling rates, so that the above T C value is approximately characteristic of both obscured and unobscured quasars. This temperature is above typical gas temperatures in elliptical galaxies and just above the virial temperatures of giant ellipticals. The general results of this work can be used for accurate calculations of the feedback effect of MBHs on both their immediate environs and the more distant interstellar medium of their host galaxies.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/1ebe38a67f96f73ea94d5a11fbb215589ce0e674

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In Astronomy and Astrophysics

Citations in the corpus

Radiative Feedback from Massive Black Holes in Elliptical Galaxies: AGN Flaring and Central Starburst Fueled by Recycled Gas (2007, background): “…al. (2005) formulae, which describe the net heating/cooling rate per unit volume Ė of a cosmic plasma in photoionization equilibriumwith a radiation field characterized by the average quasar spectral energy distribution by Sazonov et al. (2004), whose associated spectral temperature is TX ’ 2 keV.”
Stellar and Quasar Feedback in Concert: Effects on AGN Accretion, Obscuration, and Outflows (2015, methodology): “Following Sazonov et al. (2004), this can be approximated with a nearly obscuration-independent Compton temperature of TCompton ≈ 2×107 K.”
THE COSMOLOGICAL SIZE AND VELOCITY DISPERSION EVOLUTION OF MASSIVE EARLY-TYPE GALAXIES (2011, background): “However, this is an issue clearly deserving further studies on the effect of AGN feedback (e.g Sazonov et al. 2004; Di Matteo et al. 2005; Springel et al. 2005; Johansson et al. 2009a; Booth & Schaye 2009; Debuhr et al. 2010; Ostriker et al. 2010; Schaye et al. 2010), radiative feedback from stars…”
X-ray pre-ionization powered by accretion on the first black holes – I. A model for the WMAP polarization measurement (2003, methodology): “Note that we have adopted the Sazonov et al. (2004) ‘absorbed quasar spectrum’ (Fig.”
Where Are the Baryons? II. Feedback Effects (2005, methodology): “This number, eQSO, convolves together the ratio of black hole to stellar masses, 1 ; 10 3 (Kormendy & Gebhardt 2001), the radiative efficiency of black holes, 0.1 (Yu &Tremaine 2002), and the fraction of the radiative energy emitted beyond the Lyman limit, 0.25 (Sazonov et al. 2004).”
The physics of galactic winds driven by active galactic nuclei (2012, methodology): “A Compton temperature TX = 2×107 K is assumed based on the average AGN spectrum from Sazonov et al. (2004).”