S22B0077

Mapping the large-scale structure of the intergalatic medium (IGM) and the correlation with galaxies and active galactic nuclei (AGN) are instrumental to understanding how galaxies and AGN contribute to reionization. The key uncertainty is the fraction of Lyman continuum (LyC) photons escaping from galaxies into the IGM. However, even with JWST, direct confirmation at z>6 is not possible because of the intervening IGM absorption. To address this, we propose a novel photometric approach to perform 2D IGM tomography at z∼5 in the COSMOS field using extremely-deep narrow-band imaging, whereby measuring the impact of leaked LyC radiation from galaxies on the ionization state of the IGM using cross-correlation between Lyα emitters (LAEs) and Lyα forest transmission. This directly visualizes the spatial correlation between LAEs and the large-scale structure of the IGM using a reconstructed 2D tomographic map at the same cosmic volume. The dense HSC narrow-band filters available in the COSMOS field allow us to simultaneously characterize the LyC leakage, CIV, HeII emission line properties of the z∼5 LAEs, providing a panchromatic view of early galaxies and AGN activities as a function of the 2D IGM tomography just after the reionization era.

This document was translated from L^AT_EX by H^EV^EA.