ﻻ يوجد ملخص باللغة العربية
Observations of high-redshift Ly-alpha sources are a major tool for studying the high-redshift Universe. We discuss the effect of the reionizing intergalactic medium on the observability of Ly-alpha sources based on large simulations of early structure formation with radiative transfer. This takes into account self-consistently the reionization history, density, velocity and ionization structures and nonlinear source clustering. We find that all fields are highly anisotropic and as a consequence there are very large variations in opacity among the different lines-of-sight. The velocity effects, from both infall and source peculiar velocity are most important for the luminous sources, affecting the line profile and depressing the bright end of the luminosity function. The line profiles are generally asymmetric and the line centers of the luminous sources are always absorbed due to the high density of the local IGM. For both luminous and average sources the damping wing effects are of similar magnitude and remain significant until fairly late. The ionizing flux in the ionized patch surrounding a high density peak is generally strongly dominated, particularly at late times, by the cluster of faint sources, rather than the central massive galaxy. The IGM absorption does not change appreciably the correlation function of sources at high redshift. Our derived luminosity function assuming constant mass-to-light ratio provides an excellent match to the shape of the observed luminosity function at z=6.6 with faint-end slope of alpha=-1.5. The resulting mass-to-light ratio implies that the majority of sources responsible for reionization are too faint to be observed by the current surveys. (abridged)
We carried out extended spectroscopic confirmations of Ly-alpha emitters (LAEs) at z=6.5 and 5.7 in the Subaru Deep Field. Now, the total number of spectroscopically confirmed LAEs is 45 and 54 at z=6.5 and 5.7, respectively, and at least 81% (70%) o
We present a novel method to investigate cosmic reionization, using joint spectral information on high redshift Lyman Alpha Emitters (LAE) and quasars (QSOs). Although LAEs have been proposed as reionization probes, their use is hampered by the fact
In this work we model the observed evolution in comoving number density of Lyman-alpha blobs (LABs) as a function of redshift, and try to find which mechanism of emission is dominant in LAB. Our model calculates LAB emission both from cooling radiati
The highly neutral inter-galactic medium (IGM) during the Epoch of Reionization (EoR) is expected to suppress Ly$alpha$ emission with damping-wing absorption, causing nearly no Ly$alpha$ detection from star-forming galaxies at $z{sim}8$. However, spe
A major goal of observational and theoretical cosmology is to observe the largely unexplored time period in the history of our universe when the first galaxies form, and to interpret these measurements. Early galaxies dramatically impacted the gas ar