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Related papers: Neutral hydrogen in the post-reionization universe

200 papers

Hydrogen, the most abundant element in the universe, is crucial for understanding galaxy formation and evolution. The 21 cm neutral atomic hydrogen - HI spectral line maps the gas kinematics within galaxies, providing key insights into…

We use observations made with the Giant Metrewave Radio Telescope (GMRT) to probe the neutral hydrogen (HI) gas content of field galaxies in the VIMOS VLT Deep Survey (VVDS) 14h field at $z \approx 0.32$. Because the HI emission from…

The redshifted 21-cm emission by neutral hydrogen offers a unique tool for mapping structure formation in the early universe in three dimensions. Here we provide the first detailed calculation of the 21-cm emission signal during and after…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Anastasia Fialkov , Abraham Loeb

We use the photon flux and absorption tracer algorithm presented in Katz et al.~2018, to characterise the contribution of haloes of different mass and stars of different age and metallicity to the reionization of the Universe. We employ a…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 Harley Katz , Taysun Kimm , Martin G. Haehnelt , Debora Sijacki , Joakim Rosdahl , Jeremy Blaizot

Redshifted 21 cm radiation originating from the cosmological distribution of neutral hydrogen (HI) appears as a background radiation in low frequency radio observations. The angular and frequency domain fluctuations in this radiation carry…

Astrophysics · Physics 2007-05-23 Somnath Bharadwaj , SK. Saiyad Ali

We present the first results from a survey of the relative spatial distributions of galaxies, intergalactic neutral hydrogen, and intergalactic metals at high redshift. We obtained high-resolution spectra of 8 bright QSOs at 3.1<z<4.1 and…

Astrophysics · Physics 2009-11-07 K. L. Adelberger , C. C. Steidel , A. E. Shapley , M. Pettini

We estimate the signal from large scale structure at high redshifts in redshifted 21cm line. We focus on z ~ 3 and the LCDM cosmology. We assume that neutral hydrogen is to be found only in galaxies, and normalise the total content to the…

Astrophysics · Physics 2009-08-18 J. S. Bagla , Martin White

We investigate the possible presence of neutral hydrogen (HI) in intergalactic filaments at very low redshift ($z\sim 0.08$), by stacking a set of 274,712 2dFGRS galaxy pairs over 21-cm maps obtained with dedicated observations conducted…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-14 Denis Tramonte , Yin-Zhe Ma , Yi-Chao Li , Lister Staveley-Smith

We present cosmological, radiation-hydrodynamics simulations of galaxy formation during the epoch of reionization in an effort towards modelling the interstellar medium (ISM) and interpreting ALMA observations. Simulations with and without…

Astrophysics of Galaxies · Physics 2018-05-02 Harley Katz , Taysun Kimm , Debora Sijacki , Martin Haehnelt

Neutral hydrogen is an important component of the interstellar medium in elliptical galaxies as well as a potentially valuable mass tracer. Until recently, HI surveys of early-type galaxies have been sparse and inhomogeneous but this has…

Astrophysics · Physics 2007-05-23 Elaine M. Sadler , Tom Oosterloo , Raffaella Morganti

At present neutral atomic hydrogen (HI) gas in galaxies at redshifts above $z \sim 0.3$ (the extent of 21-cm emission surveys in individual galaxies) and below $z \sim 1.7$ (where the Lyman-$\alpha$ line is not observable with ground-based…

The 21cm line from the spin-flip transition of neutral hydrogen (HI) provides a unique window into the Epoch of Reionization (EoR), the final phase transition of our Universe. The Square Kilometre Array (SKA) enables precise measurements of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-09 Yannic Pietschke , Caroline Heneka , Tom Schlenker , Ayodele Ore , Benedikt Schosser

Atomic hydrogen (H I) gas, mostly residing in dark matter halos after cosmic reionization, is the fuel for star formation. Its relation with properties of host halo is the key to understand the cosmic H I distribution. In this work, we…

Astrophysics of Galaxies · Physics 2022-07-22 Zhixing Li , Hong Guo , Yi Mao

The 21-cm power spectrum of reionization is a promising probe for cosmology and fundamental physics. Exploiting this new observable, however, requires fast predictors capable of efficiently scanning the very large parameter space of…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Aurel Schneider , Timothée Schaeffer , Sambit K. Giri

Compact groups of galaxies provide a unique environment to study the evolution of galaxies amid frequent gravitational encounters. These nearby groups have conditions similar to those in the earlier universe when galaxies were assembled and…

This paper is the second in a series presenting a sample of 29 late-type dwarf galaxies observed with the Westerbork Synthesis Radio Telescope in the 21-cm line of neutral hydrogen (HI). Here we present rotation curves, maps of the velocity…

Astrophysics · Physics 2009-11-07 J. M. Stil , F. P. Israel

We compare the predictions of Horizon-AGN, a hydro-dynamical cosmological simulation that uses an adaptive mesh refinement code, to observational data in the redshift range 0<z<6. We study the reproduction, by the simulation, of quantities…

Astrophysics of Galaxies · Physics 2017-05-25 S. Kaviraj , C. Laigle , T. Kimm , J. E. G. Devriendt , Y. Dubois , C. Pichon , A. Slyz , E. Chisari , S. Peirani

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

Intensity mapping experiments are beginning to measure the spatial distribution of neutral atomic hydrogen (HI) to constrain cosmological parameters and the large-scale distribution of matter. However, models of the behaviour of HI as a…

Astrophysics of Galaxies · Physics 2024-04-30 Calvin Osinga , Benedikt Diemer , Francisco Villaescusa-Navarro , Elena D'Onghia , Peter Timbie

We present a model for the formation of the first galaxies before and after the reionization of hydrogen in the early universe. In this model, galaxy formation can only take place in dark matter haloes whose mass exceeds a…

Astrophysics of Galaxies · Physics 2020-10-07 Alejandro Benitez-Llambay , Carlos Frenk