English
Related papers

Related papers: The Morphology of Reionization in a Dynamically Cl…

200 papers

Cross-correlations between 21cm observations and galaxy surveys provide a powerful probe of reionization by reducing foreground sensitivity while linking ionization morphology to galaxies. We quantify the constraining power of 21cm-Galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Yannic Pietschke , Anne Hutter , Caroline Heneka

The critical star formation rate density required to keep the intergalactic hydrogen ionised depends crucially on the average rate of recombinations in the intergalactic medium (IGM). This rate is proportional to the clumping factor C =…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-22 Andreas H. Pawlik , Joop Schaye , Eveline van Scherpenzeel

We have recently discovered five Lyman continuum leaking galaxies at z~0.3, selected for their compactness, intense star-formation, and high [OIII]/[OII] ratio (Izotov et al. 2016ab). Here we derive their ionizing photon production…

Astrophysics of Galaxies · Physics 2016-06-29 D. Schaerer , Y. I. Izotov , A. Verhamme , I. Orlitova , T. X. Thuan , G. Worseck , N. Guseva

The fluctuations in the emission of redshifted 21cm photons from neutral inter-galactic hydrogen will provide an unprecedented probe of the reionization era. Conventional wisdom assumes that this 21cm signal disappears as soon as…

Astrophysics · Physics 2015-05-13 Stuart Wyithe , Abraham Loeb

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

We investigate the detectability of Lyman-$\alpha$ (Ly$\alpha$) emission from galaxies at the onset of cosmic reionization, aiming to understand the conditions necessary for detecting high-redshift sources like JADES-GS-z13-1-LA at $z=13$.…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-12 Yuxiang Qin , J. Stuart B. Wyithe

We present a new, on-the-fly photon flux and absorption tracer algorithm designed to directly measure the contribution of different source populations to the metagalactic UV background and to the ionisation fraction of gas in the Universe.…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-06 Harley Katz , Taysun Kimm , Martin Haehnelt , Debora Sijacki , Joakim Rosdahl , Jeremy Blaizot

The epoch of hydrogen reionization is complete by $z=5$, but its progression at higher redshifts is uncertain. Measurements of Ly$\alpha$ forest opacity show large scatter at $z<6$, suggestive of spatial fluctuations in neutral fraction…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-05 Caitlin C. Doughty , Joseph F. Hennawi , Jose Oñorbe , Frederick B. Davies , Zarija Lukić

The final stages of cosmic reionisation (EndEoR) are expected to be strongly regulated by the residual neutral hydrogen in the already ionised regions of the Universe. Its presence limits the mean distance that ionising photons can travel…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-19 Ivelin Georgiev , Garrelt Mellema , Sambit K. Giri

The propagation of cosmological ionization fronts during the reionization of the universe is strongly influenced by small-scale gas inhomogeneities due to structure formation. These inhomogeneities include both collapsed minihalos, which…

Astrophysics · Physics 2009-11-10 Ilian T. Iliev , Evan Scannapieco , Paul R. Shapiro

We present new simulations of Lyman-$\alpha$ (Ly$\alpha$) intensity maps that include Ly$\alpha$ radiative transfer in the intergalactic medium (IGM) and all significant sources of Ly$\alpha$ photons. The sources considered include…

Astrophysics of Galaxies · Physics 2025-08-29 Abigail E. Ambrose , Eli Visbal , Mihir Kulkarni , Matthew McQuinn

The reduced speed of light approximation is used in a variety of simulations of the epoch of reionization and galaxy formation. Its popularity stems from its ability to drastically reduce the computing cost of a simulation, by allowing the…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-19 P. Ocvirk , D. Aubert , J. Chardin , N. Deparis , J. Lewis

The mean free path of ionizing photons, $\lambda_{\rm mfp}$, is a key factor in the photoionization of the intergalactic medium (IGM). At $z \gtrsim 5$, however, $\lambda_{\rm mfp}$ may be short enough that measurements towards QSOs are…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-29 George D. Becker , Anson D'Aloisio , Holly M. Christenson , Yongda Zhu , Gábor Worseck , James S. Bolton

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…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-03 Sultan Hassan , Max Gronke

We use a large set of hydrodynamical simulations, combined with measurements of the Lyman alpha opacity of the IGM taken from the literature, to obtain robust estimates for the photoionization rate per hydrogen atom at z=5 and 6. We find…

Astrophysics · Physics 2009-11-13 James S. Bolton , Martin G. Haehnelt

Observations of high-redshift Ly-alpha sources are a major tool for studying the high-redshift Universe. We discuss the effect of the reionizing intergalactic medium on the observability of Ly-alpha sources based on large simulations of…

Astrophysics · Physics 2009-11-13 Ilian T. Iliev , Paul R. Shapiro , Patrick McDonald , Garrelt Mellema , Ue-Li Pen

Models of the reionization and reheating of the intergalactic medium (IGM) at redshifts $z \gtrsim 6$ continue to grow more sophisticated in anticipation of near-future 21-cm, cosmic microwave background, and galaxy survey measurements.…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-11 Jordan Mirocha , Henri Lamarre , Adrian Liu

The timing and duration of the reionization epoch is crucial to the emergence and evolution of structure in the universe. The relative roles that star-forming galaxies, active galactic nuclei and quasars play in contributing to the…

Coupled radiative-hydrodynamics simulations of the epoch of reionization aim to reproduce the propagation of ionization fronts during the transition before the overlap of HII regions. Many of these simulations use moment-based methods to…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-13 Nicolas Deparis , Dominique Aubert , Pierre Ocvirk , Jonathan Chardin , Joseph Lewis

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
‹ Prev 1 4 5 6 7 8 10 Next ›