Аннотация
By studying the large-scale structure of the bright high-redshift Lyman-break
galaxy (LBG) population it is possible to gain an insight into the role of
environment in galaxy formation physics in the early Universe. We measure the
clustering of a sample of bright ($-22.7<M_UV<-21.125$) LBGs at $z\sim6$ and
use a halo occupation distribution (HOD) model to measure their typical halo
masses. We find that the clustering amplitude and corresponding HOD fits
suggests that these sources are highly biased ($b\sim10$) objects in the
densest regions of the high-redshift Universe. Coupled with the observed rapid
evolution of the number density of these objects, our results suggest that the
shape of high luminosity end of the luminosity function is related to feedback
processes or the onset of dust obscuration - as opposed to a scenario where
these sources are predominantly rare instances of the much more numerous
$M_UV -19$ population of galaxies caught in a particularly vigorous
period of star formation. Despite investigating several variations on the
model, we struggle to simultaneously fit both the number densities and
clustering measurements. We interpret this as a signal that a refinement of the
model halo bias relation at high redshifts or the incorporation of quasi-linear
effects may be needed for future attempts at modelling the clustering and
number counts. Finally, the difference in number density between the fields
(UltraVISTA has a surface density$1.8$ times greater than UDS) is shown to
be consistent with the cosmic variance implied by the clustering measurements.
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