English
Related papers

Related papers: The Shocking Truth: The small contribution to hydr…

200 papers

Cosmological hydrodynamic simulations have significantly improved over the past several years, and we have already shown that the observed properties of Lyman-break galaxies (LBGs) at z=3 can be explained well by the massive galaxies in the…

The observed number counts of high-redshift galaxy candidates have been used to build up a statistical description of star-forming activity at redshift z >~ 7, when galaxies reionized the Universe. Standard models predict that a high…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 J. Stuart B. Wyithe , Haojing Yan , Rogier A. Windhorst , Shude Mao

The fraction of ionizing photons that escape their host galaxies to ionize hydrogen in the inter-galactic medium (IGM) is a critical parameter in analyses of the reionization era. In this paper we use the Meraxes semi-analytic galaxy…

Astrophysics of Galaxies · Physics 2023-12-11 Simon J. Mutch , Bradley Greig , Yuxiang Qin , Gregory B. Poole , J. Stuart B. Wyithe

We present the Obelisk project, a cosmological radiation-hydrodynamics simulation following the assembly and reionization of a protocluster progenitor during the first two billions of years from the big bang, down to $z = 3.5$. The…

The Epoch of Reionization marks the last major phase transition in the early Universe, during which the majority of neutral hydrogen once filling the intergalactic medium was ionized by the first galaxies. The James Webb Space Telescope is…

Astrophysics of Galaxies · Physics 2025-07-01 Cody Carr , Renyue Cen , Sophia Flury , Sally Oey , Stephan McCandliss , Allison Strom

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 explore the ability of measurements of the 21-cm power spectrum during reionization to enable the simultaneous reconstruction of the reionization history and the properties of the ionizing sources. For various sets of simulated 21-cm…

Astrophysics · Physics 2015-05-13 Rennan Barkana

We discuss new constraints on the epoch of cosmic reionization and test the assumption that most of the ionizing photons responsible arose from high redshift star-forming galaxies. Good progress has been made in charting the end of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Brant E. Robertson , Richard S. Ellis , Steven R. Furlanetto , James S. Dunlop

It is widely believed that the global baryon content and mass-to-light ratio of groups and clusters of galaxies are a fair representative of the matter mix of the universe and therefore, can be used to reliably determine the cosmic mass…

Astrophysics · Physics 2009-11-07 Xiang-Ping Wu , Yan-Jie Xue

Understanding the detailed process of cosmic reionization is one of the remaining problems in astrophysics and cosmology. Here we construct a model of cosmic reionization that includes contribution from high-$z$ galaxies and active galactic…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-30 Shintaro Yoshiura , Kenji Hasegawa , Kiyotomo Ichiki , Hiroyuki Tashiro , Hayato Shimabukuro , Keitaro Takahashi

The 21-cm signal from neutral hydrogen serves as a critical tool for unraveling the astrophysical processes that shaped cosmic dawn and the epoch of reionization. We explore the usually overlooked impact of re-scattering of 21-cm photons…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-03 Sudipta Sikder , Rennan Barkana , Anastasia Fialkov

The reionization of hydrogen in the intergalactic medium (IGM) is a crucial landmark in the history of the universe, but the processes through which it occurs remain mysterious. In particular, recent numerical and analytic work suggest that…

Astrophysics · Physics 2009-11-10 Steven Furlanetto , Lars Hernquist , Matias Zaldarriaga

The combination of the $z=0-13.5$ cosmic star formation history and active galactic nuclei (AGN) luminosity history as inferred by the James Webb Space Telescope is connected to the cosmic spectral energy distribution (CSED) to explore the…

Galaxies forming in low-mass halos are thought to be primarily responsible for reionizing the Universe during the first billion years after the Big Bang. Yet, these halos are extremely inefficient at forming stars in the nearby Universe. In…

We have compared the UV line ratios of a sample of very high redshift radio galaxies with shock and AGN photoionization models, with the goal of determining the balance between jet-induced shocks and AGN illumination in the extended…

Astrophysics · Physics 2007-05-23 M. Villar-Martin , C. N. Tadhunter , N. E. Clark

It is a widespread opinion that hydrogen reionization is mainly driven by primeval star-forming galaxies, with a minor role of high-z active galactic nuclei. Recent observations, however, challenge this notion, indicating a number of issues…

Astrophysics of Galaxies · Physics 2020-07-15 A. Grazian , E. Giallongo , F. Fiore , K. Boutsia , F. Civano , S. Cristiani , G. Cupani , M. Dickinson , F. Fontanot , N. Menci , M. Romano

The baryonic processes in galaxy evolution include gas infall onto galaxies to form neutral atomic hydrogen (HI), the conversion of HI to the molecular state (H$_2$), and, finally, the conversion of H$_2$ to stars. Understanding galaxy…

Astrophysics of Galaxies · Physics 2022-08-05 Aditya Chowdhury , Nissim Kanekar , Jayaram Chengalur , Shiv Sethi , K. S. Dwarakanath

Full radiative transfer in 3D space has been solved to pursue the reionization history in an inhomogeneous universe. It has been shown that the reionization of an inhomogeneous universe is not a prompt event, but a fairly slow process.…

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

Dark matter annihilation or decay could have a significant impact on the ionisation and thermal history of the universe. In this paper, we study the potential contribution of dark matter annihilation (s-wave- or p-wave-dominated) or decay…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-14 Hongwan Liu , Tracy R. Slatyer , Jesús Zavala

Massive stars are often found in binary systems and it has been argued that binary products boost the ionizing radiation of stellar populations. Accurate predictions for binary products are needed to understand and quantify their…

Astrophysics of Galaxies · Physics 2020-02-26 Y. Gotberg , S. E. de Mink , M. McQuinn , E. Zapartas , J. H. Groh , C. Norman