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Related papers: Lyman-alpha Emission from Structure Formation

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We study the intergalactic transmission of radiation in the vicinity of the Ly{\alpha} wavelength. Simulating sightlines through the intergalactic medium (IGM) in detailed cosmological hydrosimulations, the impact of the IGM on the shape of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Peter Laursen , Jesper Sommer-Larsen , Alexei O. Razoumov

Gas flows in and out of galaxies through their circumgalactic medium (CGM) are poorly constrained and direct observations of this faint, diffuse medium remain challenging. We use a sample of five $z$ $\sim$ 1-2 galaxy counterparts to Damped…

We examine the cooling radiation from forming galaxies in hydrodynamic simulations of the LCDM model (cold dark matter with a cosmological constant), focusing on the Ly-alpha line luminosities of high-redshift systems. Primordial…

Observations with the JWST in lensed fields have revealed that galaxies at cosmic dawn may concentrate their star formation in highly dense, compact, star clusters. The high columns and low metallicities encountered in their birth…

Astrophysics of Galaxies · Physics 2026-05-15 Shyam H Menon , Aaron Smith

High-redshift Lyman-alpha blobs (LABs) are an enigmatic class of objects that have been the subject of numerous observational and theoretical investigations. It is of particular interest to determine the dominant power sources for the…

Hydrogen emission lines can provide extensive information about star-forming galaxies in both the local and high-redshift Universe. We present a detailed Lyman continuum (LyC), Lyman-alpha (Ly{\alpha}), and Balmer line (H{\alpha} and…

It has been realised only recently that TeV emission from blazars can significantly heat the intergalactic medium (IGM) by pair-producing high-energy electrons and positrons, which in turn excite vigorous plasma instabilities, leading to a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Ewald Puchwein , Christoph Pfrommer , Volker Springel , Avery E. Broderick , Philip Chang

Galactic halos accrete material from the intergalactic medium (IGM) and part of this accretion is expected to be in the form of cool ($T\sim10^4$ K) gas. A signature of this process could reside in the detection of numerous clouds in the…

Astrophysics of Galaxies · Physics 2023-07-12 Andrea Afruni , Gabriele Pezzulli , Filippo Fraternali , Asger Grønnow

A significant fraction of the high-redshift galaxies show strong Lyman emission lines. For redshifts z>5, most known galaxies belong to this class. However, so far not much is known about the physical structure and nature of these objects.…

Astrophysics · Physics 2009-11-13 C. Tapken , I. Appenzeller , S. Noll , S. Richling , J. Heidt , E. Meinkoehn , D. Mehlert

During the epoch of reionisation the first galaxies were enshrouded in pristine neutral gas, with one of the brightest emission lines in star-forming galaxies, Lyman-$\alpha$ (Ly$\alpha$), expected to remain undetected until the Universe…

We study the visibility of the Lyman Alpha (Lya) emission line during the Epoch of Reionization (EoR). Combining galactic outflow models with large-scale semi-numeric simulations of reionization, we quantify the probability distribution…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Mark Dijkstra , Andrei Mesinger , Stuart Wyithe

We investigate Lyman-alpha (Ly$\alpha$) transmission spikes at $5.2 < z < 6.8$ using synthetic quasar spectra from the ``Cosmic Reionization On Computers" simulations. We focus on understanding the relationship between these spikes and the…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-01 Hanjue Zhu , Nickolay Gnedin , Camille Avestruz

HST imaging and slitless spectroscopy are used to examine where the strong Lyman alpha emission escapes from the interstellar medium in the starburst galaxy Mkn 357. An H-alpha image shows that the ionized gas is mostly in a global wind,…

Astrophysics · Physics 2009-11-10 William C. Keel

The Lyman-alpha emission line dominates the far-ultraviolet spectra of late-type stars and is a major source for photodissociation of important molecules including H2O, CH4, and CO2 in exoplanet atmospheres. The incident flux in this line…

Solar and Stellar Astrophysics · Physics 2015-06-12 Jeffrey L. Linsky , Kevin France , Tom Ayres

Lyman-Alpha (Lya) photons emitted in star-forming galaxies undergo complex radiative transfer through the interstellar (ISM), circumgalactic (CGM), and intergalactic medium (IGM), imprinting characteristic signatures on their observed line…

In order to shed light on how galactic properties depend on the intergalactic medium (IGM) environment traced by the Ly$\alpha$ forest, we observationally investigate the IGM-galaxy connection using the publicly available 3D IGM tomography…

During reionization, intergalactic ionization fronts (I-fronts) are sources of Ly$\alpha$ line radiation produced by collisional excitation of hydrogen atoms within the fronts. In principle, detecting this emission could provide direct…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-24 Bayu Wilson , Anson D'Aloisio , Christopher Cain , Eli Visbal , George D. Becker

Several decades of observations and discoveries have shown that high-redshift AGN and massive galaxies are often surrounded by giant Lyman-alpha nebulae extending in some cases up to 500 kpc in size. In this review, I discuss the properties…

Astrophysics of Galaxies · Physics 2017-05-31 Sebastiano Cantalupo

Hydrogen Lyman-$\alpha$ (Ly$\alpha$) emission has been one of the major observational probes for the high redshift universe, since the first discoveries of high-$z$ Ly$\alpha$ emitting galaxies in the late 1990s. Due to the strong…

Astrophysics of Galaxies · Physics 2020-12-16 Masami Ouchi , Yoshiaki Ono , Takatoshi Shibuya

Recent hydrodynamic simulations of galaxy formation reveal streams of cold (T ~ 1e4 K) gas flowing into the centers of dark matter halos as massive as 1e12-1e13.5 M_sun at redshifts z~1-3. In this paper we show that if > 20% of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Mark Dijkstra , Abraham Loeb