Chronicling the reionization history at 6≲ z ≲ 7 with emergent quasar damping wings

The spectra of high-redshift (z≳ 6) quasars contain valuable information on the progression of the Epoch of Reionization (EoR). At redshifts z<6, the observed Lyman-series forest shows that the intergalactic medium (IGM) is nearly ionized, while at z>7 the observed quasar damping wings indicate high neutral gas fractions. However, there remains a gap in neutral gas fraction constraints at 6≲ z ≲ 7 where the Lyman series forest becomes saturated but damping wings have yet to fully emerge. In this work, we use a sample of 18 quasar spectra at redshifts 6.0更多