Distinguishing AGN from starbursts as the origin of double-peaked Lyman-alpha emitters in the reionization era

We discuss the possible origin of the double-peaked profiles recently observed in Lyman-alpha emitters (LAEs) at the epoch of reionization (z greater than or similar to 6.5) from obscured active galactic nuclei (AGN). In combining the extent of the Lyman-alpha near-zones estimated from the blue peak velocity offset in these galaxies, with the ionizing emissivity of quasars at z greater than or similar to 6, we forecast the intrinsic UV and X-ray luminosities of the AGN needed to give rise to their double-peaked profiles. We also estimate the extent of the obscuration of the AGN by comparing their luminosities to those of similar quasar samples at these epochs. Future X-ray and radio observations, as well as those with the James Webb Space Telescope, will be valuable tools to test the AGN contribution to the intergalactic-scale ionization zones of high-redshift LAEs.

Automated summary

The researchers discussed the potential origin of double-peaked profiles observed in Lyman-alpha emitters during the epoch of reionization, suggesting they may come from obscured AGN. By comparing the luminosities of AGN with similar quasar samples at these epochs, they estimated the extent of AGN obscuration. Future X-ray, radio, and James Webb Space Telescope observations will be important for testing the contribution of AGN to intergalactic-scale ionization zones of high-redshift LAEs.