Zusammenfassung
We calculate Lyman Alpha Emitter (LAE) angular correlation functions (ACFs)
at $z\simeq6.6$ and the fraction of lifetime (for the 100 Myrs preceding
$z\simeq6.6$) galaxies spend as Lyman Break Galaxies (LBGs) with/without Lyman
Alpha (Ly\alpha) emission using a model that combines SPH cosmological
simulations (GADGET-2), dust attenuation and a radiative transfer code
(pCRASH). The ACFs are a powerful tool that significantly narrows the 3D
parameter space allowed by LAE Ly$\alpha$ and UV luminosity functions (LFs)
alone. With this work, we simultaneously constrain the escape fraction of
ionizing photons $f_esc=0.05-0.5$, the mean fraction of neutral hydrogen in
the intergalactic medium (IGM) $<\chi_HI>0.01$ and the dust-dependent
ratio of the escape fractions of Ly$\alpha$ and UV continuum photons
$f_\alpha/f_c=0.6-1.2$. Our results show that reionization has the largest
impact on the amplitude of the ACFs, and its imprints are clearly
distinguishable from those of $f_esc$ and $f_\alpha/f_c$. We also show that
galaxies with a critical stellar mass of $M_* = 10^8.5 (10^9.5) M_ødot$
produce enough luminosity to stay visible as LBGs (LAEs). Finally, the fraction
of time during the past 100 Myrs prior to z=6.6 a galaxy spends as a LBG with
(without) Lya emission increases with the UV magnitude (and $M_*$): considering
observed (dust and IGM attenuated) luminosities, the fraction of time a galaxy
spends as a LBG (LAE) increases from 65% to 100% (0-100%) as $M_UV$ decreases
from $M_UV = -18.0$ to $-23.5$ ($M_*$ increases from $10^8-10^10.5
M_ødot$). Thus in our model the brightest (most massive) LBGs most often show
Ly$\alpha$ emission.
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