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arXiv · 2208.04203

The effect of ionizing background fluctuations on the spatial correlations of high redshift Ly$\alpha$-emitting galaxies

Avery Meiksin·Teresita Suarez
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Abstract

We investigate the possible influence of fluctuations in the metagalactic photoionizing ultra-violet background (UVBG) on the clustering of Ly$\alpha$-emitting galaxies through the modulation of the ionization level of the gas surrounding the systems. At redshifts $z > 5$, even when assuming the reionization of the intergalactic medium has completed, the fluctuations are sufficiently large that they may non-negligibly enhance, and possibly even dominate, the angular correlation function on scales up to a few hundred arcsecs. Whilst a comparison with observations at $z \sim 5.7$ is statistically consistent with no influence of UVBG fluctuations, allowing for the fluctuations opens up the range of acceptable models to include those with relatively low bias factors for the Ly$\alpha$-emitting galaxies. In this case, the evolution in the bias factor of Ly$\alpha$-emitters over the approximate redshift range $3 < z < 7$ corresponds to a nearly constant halo mass for Ly$\alpha$-emitting galaxies of $\sim 10^{10.5}\,M_\odot$.

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Avery Meiksin, Teresita Suarez. 2022-08-08. The effect of ionizing background fluctuations on the spatial correlations of high redshift Ly$\alpha$-emitting galaxies. https://doi.org/10.1093/mnras%2Fstac2268

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