# Dark-ages reionization and galaxy formation simulation XI: Clustering and halo masses of high redshift galaxies

## TL;DR

This study models the clustering of high-redshift Lyman-break galaxies using semi-analytical simulations, finding good agreement with observations and revealing how galaxy luminosity and halo mass relate during reionization.

## Contribution

It provides the first detailed predictions of LBG clustering at z~6-8 using the Meraxes semi-analytical model, aligning with recent observational data.

## Key findings

- Predicted angular correlation functions match observations at z~6 and 7.2.
- Clustering depends on galaxy luminosity, with brighter galaxies in more massive haloes.
- Halo masses for bright LBGs remain roughly constant during reionization.

## Abstract

We investigate the clustering properties of Lyman-break galaxies (LBGs) at $z\sim6$ - $8$. Using the semi-analytical model {\scshape Meraxes} constructed as part of the Dark-ages Reionization And Galaxy-formation Observables from Numerical Simulation (DRAGONS) project, we predict the angular correlation function (ACF) of LBGs at $z\sim6$ - $8$. Overall, we find that the predicted ACFs are in good agreement with recent measurements at $z\sim 6$ and $z\sim 7.2$ from observations consisting of the Hubble eXtreme Deep Field (XDF), the Hubble Ultra-Deep Field (HUDF) and Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) field. We confirm the dependence of clustering on luminosity, with more massive dark matter haloes hosting brighter galaxies, remains valid at high redshift. The predicted galaxy bias at fixed luminosity is found to increase with redshift, in agreement with observations. We find that LBGs of magnitude $M_{{\rm AB(1600)}} < -19.4$ at $6\lesssim z \lesssim 8$ reside in dark matter haloes of mean mass $\sim 10^{11.0}$- $10^{11.5} M_{\rm \odot}$, and this dark matter halo mass does not evolve significantly during reionisation.