Related papers: Lyman-alpha blobs: polarization arising from cold …
We extend a previous study of Lyman Alpha Emitters (LAEs) based on hydrodynamical cosmological simulations, by including two physical processes important for LAEs: (a) Lyman Alpha and continuum luminosities produced by cooling of…
Using a Monte Carlo technique, we have developed a 3D lyman-alpha radiation transfer code allowing for prescribed arbitrary hydrogen density, ionisation, temperature structures, and dust distribution, and arbitrary velocity fields and UV…
A sample of 129 unresolved radio sources with ultrahigh linear polarization (>30 per cent) has been selected from the NRAO VLA Sky Survey. Such high average linear polarization is unusual in extragalactic sources. Higher resolution…
The Lyman-alpha (Ly{\alpha};1216 {\AA}) line is the brightest emission line in the quiescent solar spectrum and radiates a significant fraction of the available nonthermal energy during flares. Despite its importance, there is a lack of…
Context: Lyman $\alpha$ blobs (LABs) are large-scale radio-quiet Lyman $\alpha$ (Ly$\alpha$) nebula at high-$z$ that occur predominantly in overdense proto-cluster regions. Especially the prototypical SSA22a-LAB1 at $z=3.1$ has become an…
The conditions within the ionization front of a quasar during reionization (T ~ 30,000 K, neutral hydrogen fraction ~ 0.5) are ideal for producing Lyman-alpha emission via collisional excitation of hydrogen atoms. Observations of this…
Population III galaxies, made partly or exclusively of metal-free stars, are predicted to exist at high redshifts and may produce very strong Lya emission. A substantial fraction of these Lya photons are likely absorbed in the intergalactic…
The most remarkable class of high-redshift objects observed so far is extended Ly$\alpha$ emission-line blobs found in an over-density region at redshift 3.1. They may be either a dust-enshrouded, extreme starburst galaxy with a large-scale…
A new but rare sample of spatially extended emission line nebulae, nicknamed "Green Beans", was discovered at z~0.3 thanks to strong [OIII] emission, and subsequently shown to be local cousins of the Lyman-alpha (Lya) nebulae found at high…
We propose a new model for the extended Ly alpha blobs found recently at high redshift z ~ 3. The observational properties of these blobs are; 1) the observed Ly alpha luminosities are ~ 10^{43} h^{-2} ergs s^{-1}, 2) they appear elongated…
Lyman-$\alpha$ (Ly$\alpha$) emitting galaxies are powerful tools to probe the late stages of cosmic reionization. The observed sudden drop in Ly$\alpha$ fraction at $z>6$ is often interpreted as a sign of reionization, since the…
A Monte Carlo code to solve the transfer of Lyman alpha (Lya) photons is developed, which can predict the Lya image and two-dimensional Lya spectra of a hydrogen cloud with any given geometry, Lya emissivity, neutral hydrogen density…
This paper discusses infrared and millimetre-wavelength observations of a Lyman-alpha blob discovered by Smith & Jarvis, a candidate for ionization by the cold accretion scenario discussed in Fardal et al. and Dijkstra et al. We have…
Understanding the nature of distant Ly-alpha nebulae ("blobs") and connecting them to their present-day descendants requires constraining their number density, clustering, and large-scale environment. To measure these basic quantities, we…
At redshifts beyond z>6, as the mean fraction of neutral hydrogen x_HI in the intergalactic medium (IGM) increases, the line flux of Lyman alpha (Lya) emitters can be significantly suppressed, which can result in a decrease in the observed…
The Slug Nebula is one of the largest and most luminous Lyman-alpha (LyA) nebulae discovered to date, extending over 450 kiloparsecs (kpc) around the bright quasar UM287 at z=2.283. Characterized by high surface brightnesses over…
We report the detection of extended Lyman-alpha (Lya) haloes around 145 individual star-forming galaxies at redshifts 3<z<6 in the Hubble Ultra Deep Field observed with the Multi-Unit Spectroscopic Explorer at ESO-VLT. Our sample consists…
Recent observations show that a large number of Lyman-alpha emitters (LAEs) at high redshift z >= 3 have unusually high Lya equivalent widths (EW > 400 angstrom). However, the origin of these high EWs is an open question. Here, we…
[Abridged] With VLT/X-shooter, we obtain optical and NIR spectra of six Ly-alpha blobs at z~2.3. Using three measures --- the velocity offset between the Lya line and the non-resonant [OIII] or H-alpha line (Dv_Lya), the offset of stacked…
(Abridged) We detect the large-scale structure of Lya emission in the Universe at redshifts z=2-3.5 by measuring the cross-correlation of Lya surface brightness with quasars in SDSS/BOSS. We use a million spectra targeting Luminous Red…