The Lyman-continuum photon production efficiency in the high-redshift Universe

The Lyman-continuum photon production efficiency (xi(ion)) is a critical ingredient for inferring the number of photons available to reionize the intergalactic medium. To estimate the theoretical production efficiency in the high-redshift Universe we couple the BlueTides cosmological hydrodynamical simulation with a range of stellar population synthesis models. We find Lyman-continuum photon production efficiencies of log10(xi(ion)/erg(-1) Hz) approximate to 25.1-25.5 depending on the choice of stellar population synthesis model. These results are broadly consistent with recent observational constraints at high-redshift though favour a model incorporating the effects of binary evolution.