The clustering of \$z {\textgreater} 7\$ galaxies: Predictions from the BLUETIDES simulation. Bhowmick, A. K., Di Matteo, T., Feng, Y., & Lanusse, F. ArXiv e-prints, 1707:arXiv:1707.02312, July, 2017.
The clustering of \$z {\textgreater} 7\$ galaxies: Predictions from the BLUETIDES simulation [link]Paper  abstract   bibtex   
We study the clustering of galaxies (from \textasciitilde \$0.1\$ to a few tens Mpc scales) at high redshift (\$z{\textgreater}7\$) using the BLUETIDES simulation and compare it to current constraints from Hubble legacy and Hyper Suprime Cam (HSC) fields. BLUETIDES is the largest high resolution cosmological hydrodynamic simulation with a box length of \$400\$ \$Mpc/h\$ and \$0.7\$ trillion particles (\textasciitilde \$3\$ million star forming galaxies). We select galaxies with magnitudes consistent with the observed fields (\textasciitilde \$10{\textasciicircum}5\$ star forming galaxies at \$z\$ \textasciitilde \$8\$) and measure their clustering. The 1-halo term dominates on scales \$r {\textless} 0.1\$ \$Mpc/h\$ (\${\textbackslash}Theta {\textless} 3"\$) with non-linear effect at transition scales between the 1-halo and 2-halo term affecting scales \$0.1 {\textless} r {\textless} 20\$ \$Mpc/h\$ (\$3" {\textless} {\textbackslash}Theta {\textless} 90"\$). The predicted angular clustering amplitude of BLUETIDES galaxies is in good agreement with current measurements. The measured linear bias at \$z = 8\$ is \$7.7 {\textbackslash}pm 0.5\$ (evolving close to linearly with redshift). This is consistent with the inferred bias from observations. The typical halo masses are \$M_H\$ \textasciitilde \$2 {\textbackslash}times 10{\textasciicircum}\{10\}\$ \$M_\{{\textbackslash}odot\}/h\$, which is only slightly lower than that inferred from HOD models used to constrain observed clustering. Using the simulations we show that the current clustering measurements probe the transition between 1-halo to 2-halo regime so non-linear effects are important at all scales. We measure a strong scale dependence in the bias at scales below a few Mpc/h (\${\textbackslash}Theta {\textless} 30"\$). The occupation numbers for satellites in BLUETIDES is somewhat higher than standard HODs adopted in these analyses. That should imply a higher number of galaxies detected by JWST observing these fields. At \$z\$ \textasciitilde \$8\$ BLUETIDES predicts enhanced clustering (by factors \textasciitilde \$2\$) within the 1-halo and 1-halo to 2-halo transition scales as compared to linear HOD models; these differences increase (up to factor \textasciitilde \$10\$) at higher redshifts.
@article{bhowmick_clustering_2017,
	title = {The clustering of \$z {\textgreater} 7\$ galaxies: {Predictions} from the {BLUETIDES} simulation},
	volume = {1707},
	shorttitle = {The clustering of \$z {\textgreater} 7\$ galaxies},
	url = {http://adsabs.harvard.edu/abs/2017arXiv170702312B},
	abstract = {We study the clustering of galaxies (from {\textasciitilde} \$0.1\$ to a few tens Mpc scales) at high redshift (\$z{\textgreater}7\$) using the BLUETIDES simulation and compare it to current constraints from Hubble legacy and Hyper Suprime Cam (HSC) fields. BLUETIDES is the largest high resolution cosmological hydrodynamic simulation with a box length of \$400\$ \$Mpc/h\$ and \$0.7\$ trillion particles ({\textasciitilde} \$3\$ million star forming galaxies). We select galaxies with magnitudes consistent with the observed fields ({\textasciitilde} \$10{\textasciicircum}5\$ star forming galaxies at \$z\$ {\textasciitilde} \$8\$) and measure their clustering. The 1-halo term dominates on scales \$r {\textless} 0.1\$ \$Mpc/h\$ (\${\textbackslash}Theta {\textless} 3"\$) with non-linear effect at transition scales between the 1-halo and 2-halo term affecting scales \$0.1 {\textless} r {\textless} 20\$ \$Mpc/h\$ (\$3" {\textless}
{\textbackslash}Theta {\textless} 90"\$). The predicted angular clustering amplitude of
BLUETIDES galaxies is in good agreement with current measurements. The measured linear bias at \$z = 8\$ is \$7.7 {\textbackslash}pm 0.5\$ (evolving close to linearly with redshift). This is consistent with the inferred bias from observations. The typical halo masses are \$M\_H\$ {\textasciitilde} \$2 {\textbackslash}times 10{\textasciicircum}\{10\}\$ \$M\_\{{\textbackslash}odot\}/h\$, which is only slightly lower than that inferred from HOD models used to constrain observed clustering. Using the simulations we show that the current clustering measurements probe the transition between 1-halo to 2-halo regime so non-linear effects are important at all scales. We measure a strong scale dependence in the bias at scales below a few Mpc/h (\${\textbackslash}Theta {\textless} 30"\$). The occupation numbers for
satellites in BLUETIDES is somewhat higher than standard HODs adopted in these analyses. That should imply a higher number of galaxies detected by JWST observing these fields. At \$z\$ {\textasciitilde} \$8\$ BLUETIDES predicts enhanced clustering (by factors {\textasciitilde} \$2\$) within the 1-halo and 1-halo to 2-halo transition scales as compared to linear HOD models; these differences increase (up to factor {\textasciitilde} \$10\$) at higher redshifts.},
	journal = {ArXiv e-prints},
	author = {Bhowmick, Aklant Kumar and Di Matteo, Tiziana and Feng, Yu and Lanusse, Francois},
	month = jul,
	year = {2017},
	keywords = {Astrophysics - Cosmology and Nongalactic Astrophysics},
	pages = {arXiv:1707.02312},
}

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