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Related papers: Large 21 cm signals from AGN-dominated reionizatio…

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The cross-correlation between high redshift galaxies and 21 cm emission from the high redshift intergalactic medium (IGM) promises to be an excellent probe of the Epoch of Reionization (EoR). On large scales, the 21 cm and galaxy fields are…

Before the universe was reionized, it was likely that the spin temperature of intergalactic hydrogen was decoupled from the CMB by UV radiation from the first stars through the Wouthuysen-Field effect. If the IGM had not yet been heated…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Marcelo A. Alvarez , Ue-Li Pen , Tzu-Ching Chang

The 21 cm brightness temperature $\delta T_{\rm b}$ fluctuations from reionization promise to provide information on the physical processes during that epoch. We present a formalism for generating the $\delta T_{\rm b}$ distribution using…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-19 Raghunath Ghara , T. Roy Choudhury , Kanan K. Datta

Reionization is thought to be dominated by low mass galaxies, while direct observations of resolved galaxies probe only the most massive, rarest objects. The cross-correlation between fluctuations in the surface brightness of the cumulative…

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

We use cosmological simulations of reionization to predict the possible signal from the redshifted 21 cm line of neutral hydrogen in the pre-reionization era and to investigate the observability of this signal. We show that the separation…

Astrophysics · Physics 2009-11-10 Nickolay Y. Gnedin , Peter A. Shaver

Recent results have suggested that active galactic nuclei (AGN) could provide enough photons to reionise the Universe. We assess the viability of this scenario using a semi-numerical framework for modeling reionisation, to which we add a…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-23 Sultan Hassan , Romeel Davé , Sourav Mitra , Kristian Finlator , Benedetta Ciardi , Mario G. Santos

Upper limits from the current generation of interferometers targeting the 21-cm signal from high redshifts have recently begun to rule out physically realistic, though still extreme, models of the Epoch of Reionization (EoR). While…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-08 Jordan Mirocha , Julian B. Muñoz , Steven R. Furlanetto , Adrian Liu , Andrei Mesinger

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

A number of experiments are currently working towards a measurement of the 21 cm signal from the Epoch of Reionization. Whether or not these experiments deliver a detection of cosmological emission, their limited sensitivity will prevent…

Active Galactic Nuclei (AGN) and star-forming galaxies are leading candidates for being the luminous sources that reionized our Universe. Next-generation 21cm surveys are promising to break degeneracies between a broad range of reionization…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-20 Sultan Hassan , Adrian Liu , Saul Kohn , Paul La Plante

The 21 cm emission of neutral hydrogen is the most promising probe of the epoch of reionization(EoR). In the next few years, the SKA pathfinders will provide statistical measurements of this signal. Numerical simulations predicting these…

Astrophysics · Physics 2009-11-13 S. Baek , P. Di Matteo , B. Semelin , F. Combes , Y. Revaz

Models and simulations of the epoch of reionization predict that spectra of the 21-cm transition of atomic hydrogen will show a clear fluctuation peak, at a redshift and scale, respectively, that mark the central stage of reionization and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Anastasia Fialkov , Rennan Barkana , Eli Visbal

We consider the evolution of the sky-averaged 21 cm background during the early phases of structure formation. Using simple analytic models, we calculate the thermal and ionization histories, assuming that stellar photons dominate the…

Astrophysics · Physics 2009-11-11 Steven Furlanetto

Accurate simulations of the 21-cm signal from the Epoch of Reionization require the generation of maps at specific frequencies given the values of astrophysical and cosmological parameters. The peculiar velocities of the hydrogen atoms…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 Emma Chapman , Mario G. Santos

The cosmological process of hydrogen (HI) reionization in the intergalactic medium is thought to be driven by UV photons emitted by star-forming galaxies and ionizing active galactic nuclei (AGN). The contribution of QSOs to HI reionization…

Astrophysics of Galaxies · Physics 2016-12-21 F. Ricci , S. Marchesi , F. Shankar , F. La Franca , F. Civano

Redshifted 21cm-line signal from neutral hydrogens in the intergalactic medium (IGM) gives a direct probe of the epoch of reionization (EoR). In this paper, we investigate the potential of the variance and skewness of the probability…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-31 Kenji Kubota , Shintaro Yoshiura , Hayato Shimabukuro , Keitaro Takahashi

Cross-correlating 21cm with known cosmic signals will be invaluable proof of the cosmic origin of the first 21cm detections. As some of the widest fields available, comprising thousands of sources with reasonably known redshifts,…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-10 Caroline Heneka , Andrei Mesinger

We explore the impact of incorporating physically motivated ionisation and recombination rates on the history and topology of cosmic reionisation, by incorporating inputs from small-volume hydrodynamic simulations into a semi-numerical…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-08 Sultan Hassan , Romeel Davé , Kristian Finlator , Mario G. Santos

While limited to low spatial resolution, the next generation low-frequency radio interferometers that target 21 cm observations during the era of reionization and prior will have instantaneous fields-of-view that are many tens of square…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. G. Santos , L. Ferramacho , M. B. Silva , A. Amblard , A. Cooray

Low-frequency observatories are currently being constructed with the goal of detecting redshifted 21cm emission from the epoch of reionization. These observatories will also be able to detect intensity fluctuations in the cumulative 21cm…

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