Speaker
Description
The resonant nature of the Lya transmission results in the photons being absorbed by even trace amounts of HI in the IGM. Observed z>=5 Lya emitting galaxies (LAEs) thus reside in large ionized HII bubbles, imparting an additional clustering to the observed LAEs. The increase with redshift of the apparent clustering of LAEs can thus be exploited to place constraints on the EoR history, a crucial step in understanding reionization. In the absence of a 21-cm detection, our ability to understand the EoR is purely based on independent constraints of the EoR history. The clustering of the LAEs is a unique probe of the EoR, which is important prior to a 21-cm detection. Nevertheless, degeneracy between the evolution of the clustering of the LAEs due to cosmology (as structure formation progresses) and astrophysics (growth of the HII bubbles) results in this being a non-trivial problem.
In this work, by post-processing the Meraxes semi-analytical model outputs, we explore the feasibility of using the high-z OII & O III emission line galaxies to break this degeneracy. As these lines are not attenuated by the neutral gas in the IGM, their clustering will probe the true cosmological signal, enabling us to separate the contribution from the EoR. We explore the feasibility of this approach using ‘count-in-cell’ (CiC) statistics for a pure-parallel observational campaign with JWST. The CiC measures the integral over the 2-point correlation function and is well-suited to apply to expensive and volume-limited galaxy surveys. We explore various observing strategies for JWST with different independent random pointings and flux limits. Our fiducial simulation is calibrated with respect to various EoR constraints and the recently reported high-z OIII luminosity functions. We also explore the high-z metal emission line galaxies and their equivalent width distributions.
