Related papers: Studying the Reionization Epoch with QSO Absorptio…
Observations of the high-redshift Universe using the 21 cm line of neutral hydrogen and complimentary emission lines from the first galaxies promise to open a new door for our understanding of the epoch of reionization. We present…
The extraordinarily bright quasar PHL 1811 at a redshift z = 0.192 provides an attractive opportunity to use ultraviolet absorption-line spectroscopy to study the properties of gas systems in the local universe. An R = 20,000 far-UV…
The final stages of cosmic reionisation (EndEoR) are expected to be strongly regulated by the residual neutral hydrogen in the already ionised regions of the Universe. Its presence limits the mean distance that ionising photons can travel…
We introduce a new method for determining the influence of galaxies and active galactic nuclei (AGN) on the physical state of the intergalactic medium (IGM) at high redshift and illustrate its potential via a first application to the field…
Arguably the best hope of understanding the tail end of the reionization of the intergalactic medium (IGM) at redshift z > 6 is through the detection and characterization of the Gunn-Peterson (GP) damping wing absorption of the IGM in…
By charting the kinematic, chemical, and ionization conditions of galactic and intergalactic gas over the redshift range 0 - 4 with QSO absorption lines, the evolution of chemical abundances, the UV meta-galactic background, and the…
The Lyman-$\alpha$ forest refers to the series of absorption features observed in the spectra of distant quasars that are produced by neutral hydrogen in the intergalactic medium. Observed over a wide range of redshifts with both ground-…
We have discovered six galaxies with spectroscopically confirmed redshifts of 4.8<z<5.8 in a single 44 square arcminute field imaged deeply in R, I and z-bands. All the spectra show an emission-line in the region around 7000-8400 angstroms…
We use large-scale simulations to investigate the morphology of reionization during the final, overlap phase. Our method uses an efficient three-dimensional smoothing technique which takes into account the finite mean free path due to…
We highlight recent progress in the sophistication and diversification of cosmic dawn and reionization simulations. The application of these modeling tools to current observations has allowed us narrow down the timing of reionization, which…
The cosmic microwave background provides an image of the Universe 0.4 million years after the big bang, when atomic hydrogen formed out of free electrons and protons. One of the primary goals of observational cosmology is to obtain…
The Universe's dark ages end with the formation of the first generation of galaxies. These objects start emitting ultraviolet radiation that carves out ionized regions around them. After a sufficient number of ionizing sources have formed,…
We present an analysis of galaxy and QSO absorption line pairs toward 24 QSOs at redshifts between z~0.2 and 1 in an effort to establish the relationship between galaxies and absorption lines in physical proximity to QSOs. We demonstrate…
Lyman-alpha absorption is a prominent cosmological tool for probing both galactic halos and the intergalactic medium at high redshift. We consider a variety of sources that can be used as the Lyman-alpha emitters for this purpose. Among…
Eighteen candidates for emission line galaxies were discovered in a narrow-band infrared survey that targeted the redshifts of damped Lyman-alpha or metal lines in the spectra of quasars. The presence of emission lines is inferred from the…
We present an analysis of the proximity effect in a sample of ten 2 A resolution QSO spectra of the Ly alpha forest at <z> = 2.9. Rather than investigating variations in the number density of individual absorption lines we employ a novel…
High-resolution absorption spectroscopy toward bright background sources has had a paramount role in understanding early galaxy formation, the evolution of the intergalactic medium and the reionisation of the Universe. However, these…
We present an analysis of the evolution of the Ly alpha absorption lines in the redshift interval 0.0 to \sim 1.5 based upon a sample of 987 lines identified in the spectra of 63 QSOs obtained with the Faint Object Spectrograph on the…
A new generation of cosmological experiments will spectroscopically detect the H$\alpha$ line from ELGs at optical/near-infrared frequencies. Other emission lines will also be present, which may come from the same H$\alpha$ sample or…
The nature of the galaxies that give rise to absorption lines, such as damped Lyman-alpha systems (DLAs) or strong MgII lines, in quasar spectra is difficult to investigate in emission. Taking advantage of the total absorption of the QSO…