Linear bias forecasts for emission line cosmological surveys. (arXiv:1903.02030v1 [astro-ph.CO])
<a href="http://arxiv.org/find/astro-ph/1/au:+Merson_A/0/1/0/all/0/1">Alexander Merson</a> (JPL/IPAC), <a href="http://arxiv.org/find/astro-ph/1/au:+Smith_A/0/1/0/all/0/1">Alex Smith</a> (IRFU, CEA), <a href="http://arxiv.org/find/astro-ph/1/au:+Benson_A/0/1/0/all/0/1">Andrew Benson</a> (Carnegie), <a href="http://arxiv.org/find/astro-ph/1/au:+Wang_Y/0/1/0/all/0/1">Yun Wang</a> (IPAC), <a href="http://arxiv.org/find/astro-ph/1/au:+Baugh_C/0/1/0/all/0/1">Carlton Baugh</a> (ICC)
We forecast the linear bias for H${rm alpha}$-emitting galaxies at high
redshift. To simulate a Euclid-like and a WFIRST-like survey we place galaxies
into a large-volume dark matter halo lightcone by sampling a library of
luminosity-dependent halo occupation distributions, which is constructed using
a physically motivated galaxy formation model. We calibrate the dust
attenuation in the lightcones such that they are able to reproduce the H${rm
alpha}$ luminosity function or the H${rm alpha}$ cumulative number counts.
The angle-averaged galaxy correlation function is computed for each survey in
redshift slices of width $Delta z=0.2$. In each redshift bin the linear bias
can be fitted with a single, scale-independent value that increases with
increasing redshift. We find that the Euclid-like and WFIRST-like surveys yield
linear biases that are consistent within error, as the galaxies in the two
surveys occupy halos of similar mass $M_{200}sim 10^{11.7},h^{-1}{rm
M_{odot}} – 10^{11.9},h^{-1}{rm M_{odot}}$. Adopting a lightcone calibrated
to match the H${rm alpha}$ luminosity function, we find that the linear
biases for a Euclid-like and a WFIRST-like survey are both consistent with the
relation $b(z)simeq 0.72z+0.7$. Our bias forecasts are consistent with bias
measurements from the HiZELS survey.
We forecast the linear bias for H${rm alpha}$-emitting galaxies at high
redshift. To simulate a Euclid-like and a WFIRST-like survey we place galaxies
into a large-volume dark matter halo lightcone by sampling a library of
luminosity-dependent halo occupation distributions, which is constructed using
a physically motivated galaxy formation model. We calibrate the dust
attenuation in the lightcones such that they are able to reproduce the H${rm
alpha}$ luminosity function or the H${rm alpha}$ cumulative number counts.
The angle-averaged galaxy correlation function is computed for each survey in
redshift slices of width $Delta z=0.2$. In each redshift bin the linear bias
can be fitted with a single, scale-independent value that increases with
increasing redshift. We find that the Euclid-like and WFIRST-like surveys yield
linear biases that are consistent within error, as the galaxies in the two
surveys occupy halos of similar mass $M_{200}sim 10^{11.7},h^{-1}{rm
M_{odot}} – 10^{11.9},h^{-1}{rm M_{odot}}$. Adopting a lightcone calibrated
to match the H${rm alpha}$ luminosity function, we find that the linear
biases for a Euclid-like and a WFIRST-like survey are both consistent with the
relation $b(z)simeq 0.72z+0.7$. Our bias forecasts are consistent with bias
measurements from the HiZELS survey.
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