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Related papers: HI Signal from Reionization Epoch

200 papers

We develop and assess the potential of several powerful techniques, designed to investigate the details of reionization. First, we present a procedure to probe the neutral fraction, x_HI, using the Lyman alpha transmission statistics of…

Astrophysics · Physics 2016-08-30 Andrei Mesinger

Several experiments are underway to detect the cosmic redshifted 21-cm signal from neutral hydrogen from the Epoch of Reionization (EoR). Due to their very low signal-to-noise ratio, these observations aim for a statistical detection of the…

Intensity mapping of multiple emission lines is emerging as a new branch to astronomy, to probe both properties of ionizing sources and the medium between, in particular the intergalactic medium. For Epoch of Reionization (EoR) studies,…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-03 Caroline Heneka , Asantha Cooray

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

We study statistics of the 21-cm signal from the epoch of reionization. We propose to use [OIII] line emitting galaxies to cross-correlate with the 21-cm signal from $z = 7 - 10$. To this aim, we employ simulations of reionization obtained…

Astrophysics of Galaxies · Physics 2019-09-11 K. Moriwaki , N. Yoshida , M. B. Eide , B. Ciardi

The Lyman-$\alpha$ photons couple the spin temperature of neutral hydrogen (HI) to the kinetic temperature during the era of cosmic dawn. During this process, they also exchange energy with the medium, heating and cooling the HI. In…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-25 Janakee Raste , Shiv K. Sethi

We report on a survey for associated HI 21-cm and OH 18-cm absorption with the Giant Metrewave Radio Telescope at redshifts z = 0.2-0.4. Although the low redshift selection ensures that our targets are below the critical ultra-violet…

Astrophysics of Galaxies · Physics 2017-03-29 S. J. Curran , M. T. Whiting , J. R. Allison , A. Tanna E. M. Sadler , R. Athreya

The epoch of reionization power spectrum is expected to evolve strongly with redshift, and it is this variation with cosmic history that will allow us to begin to place constraints on the physics of reionization. The primary obstacle to the…

We use time-domain electromagnetic simulations to determine the spectral characteristics of the Hydrogen Epoch of Reionization Arrays (HERA) antenna. These simulations are part of a multi-faceted campaign to determine the effectiveness of…

We investigate self-shielding of intergalactic hydrogen against ionizing radiation in radiative transfer simulations of cosmic reionization carefully calibrated with Lyman alpha forest data. While self-shielded regions manifest as…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-13 Jonathan Chardin , Girish Kulkarni , Martin G. Haehnelt

The large number of quasars found in the Sloan Digital Sky Survey has allowed searches for elusive, clear lines of sight towards HeII Ly-alpha absorption, a sensitive probe of the intergalactic medium. The few known systems indicate that…

Line Intensity Mapping (LIM) has garnered attention as a powerful cosmological probe, with next-generation instruments such as SPHEREx preparing to map the evolution of large-scale structure during the Epoch of Reionization (EoR).…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-09 Mouza Almualla , Aaron Smith , Rahul Kannan , Lars Hernquist , Enrico Garaldi , Adam Lidz , Kevin Lorinc , Jennifer Yik Ham Chan , Mark Vogelsberger

An appealing approach for studying the reionization history of the Universe is to measure the redshift evolution of the Lyman-alpha fraction, the percentage of Lyman-break selected galaxies that emit appreciably in the Ly-alpha line. This…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Jessie Taylor , Adam Lidz

Observationally mapping the relation between galaxies and the intergalactic medium (IGM) is of key interest for studies of cosmic reionization. Diffuse hydrogen gas has typically been observed in HI Lyman-$\alpha$ (Ly$\alpha$) absorption in…

The redshifted 21-cm signal from the epoch of reionization (EoR) directly probes the ionization and thermal states of the intergalactic medium during that period. In particular, the distribution of the ionized regions around the radiating…

The cross-correlation between the 21 cm emission from the high-redshift intergalactic medium and the near-infrared (NIR) background light from the high-redshift galaxies promises to be a powerful probe of cosmic reionization. In this paper,…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Xiao-Chun Mao

HII regions made of gas ionized by radiations from young massive stars, are widely distributed in the Milky Way. They are tracers for star formation, and their distributions are correlated with the Galactic spiral structure. Radio…

Astrophysics of Galaxies · Physics 2021-11-03 Chuan-Peng Zhang , Jin-Long Xu , Guang-Xing Li , Li-Gang Hou , Nai-Ping Yu , Peng Jiang

We investigate the physical state of HI absorbing gas at low redshift (z = 0.25) using a subset of cosmological, hydrodynamic simulations from the OWLS project, focusing in particular on broad (b_HI > 40 km/s) HI Lyman-Alpha absorbers…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Thorsten Tepper-García , Philipp Richter , Joop Schaye , Craig M. Booth , Claudio Dalla Vecchia , Tom Theuns

We present new measurements of the intensity of the ionizing ultraviolet background and the global emissivity of ionizing photons over 2 < z < 5. Our results are based on a suite of updated measurements of physical properties of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 George D. Becker , James S. Bolton