Evolution of the Quasar Luminosity Function: Implications for EoR-21cm

Abstract

<jats:title>Abstract</jats:title><jats:p>We present predictions for the spatial distribution of 21 cm brightness temperature fluctuations from high-dynamic-range simulations for AGN-dominated reionization histories that have been tested against available <jats:italic>Lyα</jats:italic> and CMB data. We model AGN by extrapolating the observed M<jats:sub>bh</jats:sub>–σ relation to high redshifts and assign them ionizing emissivities consistent with recent UV luminosity function measurements. AGN-dominated reionization histories increase the variance of the 21 cm emission by a factor of up to ten compared to similar reionization histories dominated by faint galaxies, to values close to 100 mK<jats:sup>2</jats:sup> at scales accessible to experiments (<jats:italic>k</jats:italic> ≲ 1 cMpc<jats:sup>−1</jats:sup><jats:italic>h</jats:italic>). This is lower than the sensitivity reached by ongoing experiments by only a factor of about two or less. AGN dominated reionization should be easily detectable by LOFAR (and later HERA and SKA1) at their design sensitivity.</jats:p>