Constraints on the ionization sources of the high-redshift intergalactic medium.
Monthly Notices of the Royal Astronomical Society 356 (2), 596-606.
(dot-dashed line) and (short-dashed line). These latter three rates are shown for αS= 1. For alternative values, they should be multiplied by the factor αS.
Also shown are the predicted contributions from QSO sources, assuming
either a PLE model (filled squares) or PDE model (open squares) for the
QSO luminosity function (see Section 3 of Meiksin 2005).
The evolution of the comoving production rate of ionizing
photons. The required rate inferred from measurements of the mean
transmitted Lyα flux is shown by the solid line. The long-dashed line
shows the required source rate if diffuse recombination radiation from
the IGM boosts the total metagalactic photoionization rate by 50 per
cent. Also shown are the minimal ionizing photon production rate nHt1H required to ionize the IGM over a Hubble time (dotted line), and the rate of recombinations for clumping factors of