Related papers: The Galaxy Proximity Effect in the Lyman-alpha For…
We have performed high-resolution hydrodynamic simulations of the Lyman-alpha forest in a variety of popular cold dark matter dominated cosmologies, including a low density and a vacuum-dominated model. The fluctuation amplitude of these…
Galactic outflows are critical to our understanding of galaxy formation and evolution. However the details of the underlying feedback process remain unclear. We compare Ly$\alpha$ observations of the circumgalactic medium (CGM) of Lyman…
We present observations of a peculiar Lyman alpha-emitting galaxy at redshift 3.344, discovered in a deep, blind spectroscopic survey for faint Lyman alpha emitters with the Magellan II telescope in the Hubble Ultra Deep Field (HUDF). The…
A simple consistency argument for hypothesis of the galactic halo origin of the Ly-alpha forest absorption lines is advanced, based on the recent determination of column-density vs. impact parameter relation for the low-redshift gaseous…
The intergalactic medium (IGM) in the vicinity of galaxy protoclusters are interesting testbeds to study complex baryonic effects such as gravitational shocks and feedback. Here, we utilize hydrodynamical simulations from the SIMBA and The…
Although quasar absorbers, and in particular Damped Lyman-alpha systems (DLAs) have proven a valuable tool to study the early Universe, their exact nature is so far poorly constrained. It has been suggested that outflows in galaxies might…
We measure the redshift-dependent luminosity function and the comoving radial density of galaxies in the Sloan Digital Sky Survey Data Release 1 (SDSS DR1). Both measurements indicate that the apparent number density of bright galaxies…
We present a statistical analysis of Ly$\alpha$ absorption using 581 galaxies at $z=4.5$--13 observed with multiple JWST/NIRSpec spectroscopy programs, including JADES, UNCOVER, CEERS, and GO/DDT. We carefully construct composite spectra…
We investigate the properties of the HI Ly-a absorption systems (Ly-a forest) within and around galaxy voids at z<0.1. We find a significant excess (>99% c.l.) of Ly-a systems at the edges of galaxy voids with respect to a random…
Projected quasar galaxy pairs provide powerful means to study the circumgalactic medium (CGM) that maintains the relics of galactic feedback and the accreted gas from the intergalactic medium. Here, we study the nature of a Lyman Limit…
The relation between high redshift galaxies and QSO absorption systems is discussed in the context of hierarchical galaxy formation. It is demonstrated that imprints of the reionization history of the universe are detectable in the…
We report on the results of a search for CO(3-2) emission from the galaxy counterpart of a high-metallicity Damped Ly-alpha Absorber (DLA) at z=2.5832 towards the quasar Q0918+1636. We do not detect CO emission from the previously…
We present some statistical features of the large number of \lya absorption lines detected in high redshift quasar spectra, obtained by using the multifractal approach. In the analysed sample of 12 QSO sight--lines, 11 show scaling…
In Lyman-alpha forest measurements it is generally assumed that quasars are mere background light sources which are uncorrelated with the forest. Gravitational lensing of the quasars violates this assumption. This effect leads to a…
Galaxy protoclusters, which will eventually grow into the massive clusters we see in the local universe, are usually traced by locating overdensities of galaxies. Large spectroscopic surveys of distant galaxies now exist, but their…
The isotropy of the Lyman-alpha forest in real-space uniquely provides a measurement of cosmic geometry at z > 2. The angular diameter distance for which the correlation function along the line of sight and in the transverse direction agree…
The distribution of absorption lines in the spectra of distant quasars, called the Lyman-$\alpha$ (Ly-$\alpha$) forest, is a unique probe of cosmology and the intergalactic medium at high redshifts and small scales. The statistical power of…
Gravitational lensing of an optical QSO by a spiral galaxy is often counteracted by dust obscuration, since the line-of-sight to the QSO passes close to the center of the galactic disk. The dust in the lens is likely to be correlated with…
Recent observations of the Lyman-alpha forest show large-scale spatial variations in the intergalactic Lyman-alpha opacity that grow rapidly with redshift at z>5, far in excess of expectations from empirically motivated models. Previous…
Semi-analytical models of galaxy formation based on hierarchical clustering now make a wide range of predictions for observable properties of galaxies at low and high redshift. This article concentrates on 2 aspects: (1) Self-consistent…