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Related papers: Testing the Topology of Reionization

200 papers

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…

Astrophysics of Galaxies · Physics 2015-09-16 Rachael Alexandroff , Timothy Heckman , Sanchayeeta Borthakur , Roderik Overzier , Claus Leitherer

The increasingly neutral intergalactic gas at $z>6$ impacts the Lyman-$\alpha$ flux observed from galaxies. One luminous galaxy, COLA1, stands out because of its unique double-peaked Ly$\alpha$ line at $z=6.6$, unseen in any simulation of…

The nature of the interaction between galaxies and the intergalactic medium (IGM) is one of the most fundamental problems in astrophysics. The accretion of gas onto galaxies provides fuel for star formation, while galactic winds transform…

Astrophysics · Physics 2009-11-10 Steven Furlanetto , Joop Schaye , Volker Springel , Lars Hernquist

While most of the inter-galactic medium (IGM) today is permeated by ionized hydrogen, it was largely filled with neutral hydrogen for the first 700 million years after the Big Bang. The process that ionized the IGM (cosmic reionization) is…

During the epoch of reionization (EoR), the 21-cm signal allows direct observation of the neutral hydrogen (HI) in the intergalactic medium (IGM). In the post-reionization era, this signal instead probes HI in galaxies, which traces the…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-20 Sambit K. Giri , Michele Bianco , Timothée Schaeffer , Ilian T. Iliev , Garrelt Mellema , Aurel Schneider

Deep surveys have recently discovered galaxies at the tail end of the epoch of reionization. In the near future, these discoveries will be complemented by a new generation of low-frequency radio observatories that will map the distribution…

Astrophysics · Physics 2009-11-11 Stuart Wyithe , Avi Loeb

We present the analysis of deep HST multi-band imaging of the BDF field specifically designed to identify faint companions around two of the few Ly-alpha emitting galaxies spectroscopically confirmed at z~7 (Vanzella et al. 2011). Although…

With improving telescopes, it may now be possible to observe the Epoch of Reionization in multiple ways. We examine two of these observables - the excess light in the near-infrared background that may be due to high redshift stars and…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-19 Elizabeth R. Fernandez , Saleem Zaroubi , Ilian T. Iliev , Garrelt Mellema , Vibor Jelic

Using 3D radiative transfer calculations on the reionization of an inhomogeneous universe, QSO absorption line systems are simulated and they are compared with observations of Ly$\alpha$ continuum depression at high redshifts. By this…

Astrophysics · Physics 2007-05-23 M. Umemura , T. Nakamoto , H. Susa

The next generation of telescopes aim to directly observe the first generation of galaxies that initiated the reionization process in our Universe. The Lyman Alpha (Lya) emission line is robustly predicted to be the most prominent intrinsic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Mark Dijkstra , Stuart Wyithe

Spatial variations in the Lyman-$\alpha$ forest opacity at $z<6$ seem to require a late end to cosmic reionization. In this picture, the universe contains neutral hydrogen 'islands' of up to 100 cMpc$/h$ in extent down to redshifts as low…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-06 Janakee Raste , Girish Kulkarni , Catherine A. Watkinson , Laura C. Keating , Martin G. Haehnelt

Multiply connected space sections of the universe on a scale smaller than the horizon size can leave an imprint on cosmic microwave background polarization maps, in such a way that the so-called ``circles-in-the-sky'' method can be used to…

We show how the morphological analysis of the maps of the secondary CMB anisotropies can detect an extended period of ``smoldering'' reionization, during which the universe remains partially ionized. Neither radio observations of the…

Astrophysics · Physics 2008-11-26 Nickolay Y. Gnedin , Sergei F. Shandarin

We consider the effect of reionization on the clustering properties of galaxy samples at intermediate redshifts (z~0.3-5.5). Current models for the reionization of intergalactic hydrogen predict that overdense regions will be reionized…

Astrophysics · Physics 2019-08-19 Stuart Wyithe , Avi Loeb

We compute the bispectra of the 21cm signal during the Epoch of Reionization for three different reionization scenarios that are based on a dark matter N-body simulation combined with a self-consistent, semi-numerical model of galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Anne Hutter , Catherine A. Watkinson , Jacob Seiler , Pratika Dayal , Manodeep Sinha , Darren J. Croton

The effect of line overlap in the Lyman and Werner bands, often ignored in galactic studies of the atomic-to-molecular transition, greatly enhances molecular hydrogen self-shielding in low metallicity environments, and dominates over dust…

Astrophysics of Galaxies · Physics 2016-08-01 Nickolay Y. Gnedin , Bruce T. Draine

We consider cosmological models with a power spectrum of perturbations featuring an enhanced amplitude on dwarf galaxy scales (with a "bump" or a "tilt"). Early formation of a large number of galaxies in such models, compared to the…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-27 O. R. Skorikov , S. V. Pilipenko , M. V. Tkachev

Cosmic reionization marks a critical epoch when the first galaxies ionized the intergalactic medium through the escape of Lyman continuum (LyC) radiation. Young, massive star clusters are believed to be the primary LyC sources, yet the…

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Zheng Zheng , Renyue Cen , David Weinberg , Hy Trac , Jordi Miralda-Escude

We study CMB secondary anisotropies produced by inhomogeneous reionization by means of cosmological simulations coupled with the radiative transfer code CRASH. The reionization history is consistent with the WMAP Thomson optical depth…

Astrophysics · Physics 2009-11-10 R. Salvaterra , B. Ciardi , A. Ferrara , C. Baccigalupi
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