Related papers: On the Diffuse Lyman-alpha Halo Around Lyman-alpha…
We present detailed predictions for the properties of Ly-alpha-emitting galaxies in the framework of the Lambda-CDM cosmology, calculated using the semi-analytical galaxy formation model GALFORM. We explore a model which assumes a top-heavy…
The resonantly scattered Lyman-$\alpha$ line illuminates the extended halos of neutral hydrogen in the circumgalactic medium of galaxies. We present integral field Keck Cosmic Web Imager observations of double-peaked, spatially extended…
Spatially extended halos of H I Ly$\alpha$ emission are now ubiquitously found around high-redshift star-forming galaxies. But our understanding of the nature and powering mechanisms of these halos is still hampered by the complex radiative…
We propose to infer ionising continuum leaking properties of galaxies by looking at their Lyman-alpha line profiles. We carry out Lyman-alpha radiation transfer calculations in two models of HII regions which are porous to ionising…
We explore the properties of high-redshift Lyman-alpha emitters (LAE), and their link with the Lyman-Break galaxy population (LBG), using a semi-analytic model of galaxy formation that takes into account resonant scattering of Lya photons…
Ly$\alpha$ emission is the strongest tracer of recombining ionized hydrogen in young, star-forming galaxies, but its origin is still debated. Ly$\alpha$ arises when emitted photons scatter in neutral hydrogen and, so far, observational…
Based on the Sloan Digital Sky Survey Data Release 16, we have detected the large-scale structure of Ly$\alpha$ emission in the Universe at redshifts $z = 2$--3.5 by cross-correlating quasar positions and Ly$\alpha$ emission imprinted in…
We present the first results from the X-SHOOTER Lyman-$\alpha$ survey at $z=2$ (XLS-$z2$). XLS-$z2$ is a deep spectroscopic survey of 35 Lyman-$\alpha$ emitters (LAEs) utilising $\approx90$ hours of exposure time with VLT/X-SHOOTER and…
Lyman-$\alpha$ photons are resonantly scattered by neutral hydrogen, and may therefore trace both the spatial extent and the kinematics of the gas surrounding galaxies. We present new observations of the extended Ly$\alpha$ halo of…
The recently discovered population of ultra-faint extended line emitters can account for the majority of the incidence rate of Damped Lyman Alpha systems (DLAs) at z ~ 3 if the line emission is interpreted as Ly alpha. We show here that a…
The Lyman-$\alpha$ (Lya) line of hydrogen is a well-known tracer of galaxies at high-z. However, the connection between Lya observables and galaxy properties has not fully been established, limiting the use of the line to probe the physics…
We have obtained the first constraints on extended Ly-alpha emission at z ~ 1 in a sample of five radio galaxies. We detect Ly-alpha emission from four of the five galaxies. The Ly-alpha luminosities range from 0.1 - 4 times 10^43 erg/s and…
Extended Ly$\alpha$ emission is commonly observed around star-forming galaxies, opening a window for probing the neutral hydrogen gas in the circumgalactic medium (CGM). In this paper, we develop a prescription of spherically symmetric CGM…
Lyman Alpha Emitters (LAEs) are star-forming galaxies that efficiently probe the spatial distribution of galaxies in the high redshift universe. The spatial clustering of LAEs reflects the properties of their individual host dark matter…
Lyman-alpha (Ly{\alpha}) photons from ionizing sources and cooling radiation undergo a complex resonant scattering process that generates unique spectral signatures in high-redshift galaxies. We present a detailed Ly{\alpha} radiative…
The Lyman $\alpha$ (Ly$\alpha$) line from high-redshift galaxies is a powerful probe of the Epoch of Reionization (EoR). Neutral hydrogen in the intergalactic medium (IGM) can significantly attenuate the emergent Ly$\alpha$ line, even in…
Hydrogen Ly${\alpha}$ haloes (LAHs) are commonly used as a tracer of the circumgalactic medium (CGM) at high redshifts. In this work, we aim to explore the existence of Ly${\alpha}$ haloes around individual UV-selected galaxies, rather than…
We review the Lyan alpha emission in local star-forming galaxies. In most cases as already shown by the IUE, the emission is absent or much weaker than expected. This occurs because Lyman alpha photons can be resonantly scattered by the…
Scattering of Lyman Alpha (hereafter Lya) photons by neutral hydrogen gas in a single outflowing 'supershell' around star forming regions often explains the shape and offset of the observed Lya emission line from galaxies. We compute the…
We report the detection at 850um of the central source in SSA22-LAB1, the archetypal Lyman-alpha Blob (LAB), a 100kpc-scale radio-quiet emission-line nebula at z=3.1. The flux density of the source, $S_{850}=4.6\pm1.1$mJy implies the…