Related papers: Simulations of the Intergalactic Medium
The local intensity of the 21 cm signal emitted during the Epoch of Reionization that will be mapped by the SKA is modulated by the amount of neutral hydrogen. Consequently, understanding the process of reionization of the intergalactic…
We discuss observations of the first galaxies, within cosmic reionization, at centimeter and millimeter wavelengths. We present a summary of current observations of the host galaxies of the most distant QSOs ($z \sim 6$). These observations…
The Gunn-Peterson effect, absorption of Lya photons by a homogeneous component of the intergalactic medium (IGM), potentially provides a test of Big Bang Nucleosynthesis (BBN). With a lower limit on the UV radiation field estimated from the…
Searches for Lyman-alpha emission lines are among the most effective ways to identify high-redshift galaxies. They are particularly interesting because they probe not only the galaxies themselves but also the ionization state of the…
The history of the transition from a neutral intergalactic medium (IGM) to one that is almost fully ionized can reveal the character of cosmological ionizing sources. We study the evolution of the volume filling factor of HII and HeIII…
Recently, Pello et al. (2004) claimed to have discovered a galaxy at a redshift z=10, and identified a feature in its spectrum with a hydrogen Lyman-alpha emission line. If this identification is correct, we show that the intergalactic…
Numerical simulations predict that a large number of baryons reside in intergalactic space at temperatures between 10^5-10^7 K. Highly-ionized metals, such as O VII and O VIII, are good tracers of this ``warm-hot intergalactic medium'', or…
An appealing approach for studying the reionization history of the Universe is to measure the redshift evolution of the Lyman-alpha fraction, the percentage of Lyman-break selected galaxies that emit appreciably in the Ly-alpha line. This…
Cosmological hydrodynamic simulations have significantly improved over the past several years, and we have already shown that the observed properties of Lyman-break galaxies (LBGs) at z=3 can be explained well by the massive galaxies in the…
The number of detected baryons in the Universe at z<0.5 is much smaller than predicted by standard big bang nucleosynthesis and by the detailed observation of the Lyman alpha forest at red-shift z=2. Hydrodynamical simulations indicate that…
We consider the evolution of the sky-averaged 21 cm background during the early phases of structure formation. Using simple analytic models, we calculate the thermal and ionization histories, assuming that stellar photons dominate the…
The circumgalactic medium (CGM), which harbors > 50% of all the baryons in a galaxy, is both the reservoir of gas for subsequent star formation and the depository of chemically processed gas, energy, and angular momentum from feedback. As…
We determine the abundance of i'-band drop-outs in the HST/ACS GOODS surveys and the Hubble Ultra Deep Field (UDF). The majority of these sources are likely to be z~6 galaxies whose flux decrement arises from Lyman-alpha absorption. We have…
Using the CoDa II simulation, we study the Ly$\alpha$ transmissivity of the intergalactic medium (IGM) during reionization. At $z>6$, a typical galaxy without an active galactic nucleus fails to form a proximity zone around itself due to…
Observations at long wavelengths, in the wide interval from a few to 1000 micron, are essential to study diffuse media in galaxies, including all kinds of atomic, ionic and molecular gases and dust grains. Hence they are particularly suited…
We review the current state of empirical knowledge of the total budget of baryonic matter in the Universe as observed since the epoch of reionization. Our summary examines on three milestone redshifts since the reionization of H in the IGM,…
The small-scale structure of baryons in the intergalactic medium is intimately linked to their past thermal history. Prior to the $\gtrsim10^4$ K photoheating during the epoch of reionization, cold baryons may have closely traced the clumpy…
The thermal history and structure of the intergalactic medium (IGM) at $z \geq 4$ is an important boundary condition for reionization, and a key input for studies using the Ly$\alpha$ forest to constrain the masses of alternative dark…
(Abridged) In these lectures aimed for non-specialists, I review progress in understanding how galaxies form and evolve. Both the star formation history and assembly of stellar mass can be empirically traced from redshifts z~6 to the…
Near-infrared observations of Lyman-break galaxies at redshifts z~3 are beginning to provide constraints on ages, star-formation histories, dust content, metallicities, and stellar masses. At present, uncertainties of more than an order of…