Related papers: Lyman-alpha emission as a tool to study high redsh…
Lyman-alpha (Lya) photons that escape the interstellar medium of star-forming galaxies may be resonantly scattered by neutral hydrogen atoms in the circumgalactic and intergalactic media, thereby increasing the angular extent of the…
We present a new model for high redshift Lyman-Alpha Emitters (LAEs) in the cosmological context which takes into account the resonant scattering of Ly-a photons through expanding gas. The GALICS semi-analytic model provides us with the…
The standard $\rm \Lambda$CDM cosmological model predicts that a large amount of diffuse neutral hydrogen distributes in cosmic filaments, which could be mapped through Lyman-alpha (Ly$\alpha$) emission observations. We use the…
We study the distribution of low-redshift Ly$\alpha$ clouds in a CDM model using numerical simulations including photoionization and cooling of the baryonic component. The ionizing background is found to be efficient enough to keep most of…
We present Ly $\alpha$ imaging of 45 low redshift star-forming galaxies observed with the Hubble Space Telescope. The galaxies have been selected to have moderate to high star formation rates using far-ultraviolet (FUV) luminosity and \ha…
In this paper we investigate the possible reasons why HI 21-cm absorption in damped Lyman-alpha systems (DLAs) has only been detected at low redshift... We suggest that the lack of 21-cm absorption detections at high redshift arises from…
The Lyman Alpha damping wing is seen in absorption against the spectra of high-redshift galaxies. Modeling of this wing is a way to measure the volume neutral hydrogen fraction of the Universe, as well as to measure the strength of HI…
Spectroscopy of QSO absorption lines provides essential observational input for the study of nucleosynthesis and chemical evolution of galaxies at high redshift. But new observations may indicate that present chemical abundance data are…
The Ly$\alpha$ emission has emerged as a powerful tool for probing diffuse gas within the large-scale structure of the universe. In this paper, we investigate cosmic Ly$\alpha$ emission by post-processing cosmological simulations from…
I provide an overview about star-forming galaxies at high redshift and their physical properties. Starting from the populations of Ly-$\alpha$ emitters and Lyman break galaxies, I summarize their common features and distinction. Then I…
We investigate a model for the high-ionization state gas associated with observed damped Lyman-alpha systems, based on a semi-analytic model of galaxy formation set within the paradigm of hierarchical structure formation. In our model, the…
We have used the Very Long Baseline Array to image 18 quasars with foreground damped Lyman-$\alpha$ systems (DLAs) at 327, 610 or 1420 MHz, to measure the covering factor $f$ of each DLA at or near its redshifted HI 21cm line frequency.…
Damped Lyman-$\alpha$ absorbers (DLAs) with molecular hydrogen have been probed in detail through both spectroscopic observations and numerical modelling. However, such H$_2$ absorbers are quite sparse at very high redshifts. We identify…
We present a comparison between the observed properties of damped Lyman alpha systems (DLAs) and the predictions of simple models for the evolution of present day disk galaxies, including both low and high surface brightness galaxies. We…
Various types of galaxies observed in the cosmological scales show P-Cygni type profiles in the Lyman alpha emission lines. A Monte Carlo code is developed to investigate the Lyman alpha line transfer in an optically thick and moving medium…
Using the Atacama Large Millimeter/sub-millimeter Array, we have detected CO(3-2) line and far-infrared continuum emission from a galaxy associated with a high-metallicity ([M/H] = -0.27) damped Ly-alpha absorber (DLA) at z =2.19289. The…
We present an exhaustive census of Lyman alpha (Ly$\alpha$) emission in the general galaxy population at $3<z<4.6$. We use the Michigan/Magellan Fiber System (M2FS) spectrograph to study a stellar mass (M$_*$) selected sample of 625…
A population of early star-forming galaxies is the leading candidate for the re-ionization of the universe. It is still unclear what conditions and physical processes would enable a significant fraction of the ionizing photons to escape…
In this article we first outline the mounting evidence that a significant fraction of the ionizing photons emitted by OB stars within HII regions escape from their immediate surroundings and explain how an HII region structure containing…
Identifying the mechanisms driving the escape of Lyman Continuum (LyC) photons is crucial to find Lyman Continuum Emitter (LCE) candidates. To understand the physical properties involved in the leakage of LyC photons, we investigate the…