Consistent modelling of the meta-galactic UV background and the thermal/ionization history of the intergalactic medium

Understand

Recent observations suggest that hydrogen reionization ends late ($z \simeq 6$) and proceeds quickly.

• We present here a new model of the meta-galactic UV/X-ray background (UVB) that is consistent with this.
• It adopts the most recent determinations of the ionizing emissivity due to stars and AGN, as well as of the HI absorber column density distribution.
• Another major improvement is a new treatment of the intergalactic medium (IGM) opacity for ionizing photons that is able to consistently capture the transition from a neutral to an ionized IGM.