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Related papers: Detecting ionized bubbles in redshifted 21 cm maps

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Characterizing the epoch of reionization (EoR) at $z\gtrsim 6$ via the redshifted 21 cm line of neutral Hydrogen (HI) is critical to modern astrophysics and cosmology, and thus a key science goal of many current and planned low-frequency…

A number of radio interferometers are currently being planned or constructed to observe 21 cm emission from reionization. Not only will such measurements provide a detailed view of that epoch, but, since the 21 cm emission also traces the…

The locations of Ly-$\alpha$ emitting galaxies (LAEs) at the end of the Epoch of Reionisation (EoR) are expected to correlate with regions of ionised hydrogen, traced by the redshifted 21~cm hyperfine line. Mapping the neutral hydrogen…

We examine the prospects for studying the pre-reionization intergalactic medium (IGM) through the so-called 21 cm forest in spectra of bright high-redshift radio sources. We first compute the evolution of the mean optical depth for models…

Astrophysics · Physics 2009-11-11 Steven Furlanetto

The Green Bank Telescope HII Region Discovery Survey has doubled the number of known HII regions in the Galactic zone 343deg.\leql\leq67deg. with |b|\leq1deg. We detected 603 discrete hydrogen radio recombination line (RRL) components at…

Astrophysics of Galaxies · Physics 2015-05-27 L. D. Anderson , T. M. Bania , Dana S. Balser , Robert T. Rood

We present volume-averaged neutral hydrogen fractions $x_{\rm \HI}$ and ionized bubble radii $R_{\rm b}$ measured with Ly$\alpha$ damping wing absorption of galaxies at the epoch of reionization. We combine JWST/NIRSpec spectra taken by…

Astrophysics of Galaxies · Physics 2024-06-14 Hiroya Umeda , Masami Ouchi , Kimihiko Nakajima , Yuichi Harikane , Yoshiaki Ono , Yi Xu , Yuki Isobe , Yechi Zhang

The optical depth parameterisation is typically used to study the 21-cm signals associated with the properties of the neutral hydrogen (HI) gas and the ionisation morphology during the Epoch of Reionisation (EoR), without solving the…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-21 Kinwah Wu , Qin Han , Jennifer Y. H. Chan

We use hydrodynamic cosmological simulations in a 9.6 Mpc box to explore the evolution of the intergalactic medium (IGM) transmissivity from z=2 through the epoch of reionization. Reionization is achieved through an ultraviolet background…

Astrophysics · Physics 2009-11-10 Pascal Paschos , Michael L. Norman

Spectra of the highest redshift galaxies taken with JWST are now allowing us to see into the heart of the reionization epoch. Many of these observed galaxies exhibit strong damping wing absorption redward of their Lyman-$\alpha$ emission.…

Astrophysics of Galaxies · Physics 2023-08-14 Laura C. Keating , James S. Bolton , Fergus Cullen , Martin G. Haehnelt , Ewald Puchwein , Girish Kulkarni

The central overlap phase of cosmological hydrogen reionization is fundamentally a change in the topology of ionized regions. Before overlap, ionized bubbles grew in isolation. During overlap, they merge into a percolating ionized medium,…

Astrophysics · Physics 2007-08-23 James E. Rhoads

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

The cross-correlation between fluctuations in the electron scattering optical depth $\tau_{\rm es}$ as probed by future Cosmic Microwave Background (CMB) experiments, and fluctuations in the 21cm differential brightness temperature $\Delta…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-07 Anirban Roy , Andrea Lapi , David Spergel , Soumen Basak , Carlo Baccigalupi

The introduction of low-frequency radio arrays is expected to revolutionize the study of the reionization epoch. Observation of the contrast in redshifted 21cm emission between a large HII region and the surrounding neutral inter-galactic…

Astrophysics · Physics 2009-11-13 Stuart Wyithe

We use numerical simulations of cosmic reionization and radiative processes related to the HI 21 cm emission line to produce synthetic radio maps as seen by next generation radio telescopes that will operate at low radio frequencies (e.g.…

Astrophysics · Physics 2009-11-11 M. Valdes , B. Ciardi , A. Ferrara , M. Johnston-Hollitt , H. Rottgering

We use the latest multi-redshift ($z=6.5-8.7$) upper limits on the 21-cm signal from the Murchison Widefield Array (MWA) to explore astrophysical models which are inconsistent with the data. These upper limits are achieved using 298 h of…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-25 Bradley Greig , Cathryn M. Trott , Nichole Barry , Simon J. Mutch , Bart Pindor , Rachel L. Webster , J. Stuart B. Wyithe

The upcoming Square Kilometre Array Observatory (SKAO) will produce images of neutral hydrogen distribution during the epoch of reionization by observing the corresponding 21-cm signal. However, the 21-cm signal will be subject to…

Instrumentation and Methods for Astrophysics · Physics 2024-02-29 Michele Bianco , Sambit. K. Giri , David Prelogović , Tianyue Chen , Florent G. Mertens , Emma Tolley , Andrei Mesinger , Jean-Paul Kneib

A number of large current experiments aim to detect the signatures of the Cosmic Reionization at redshifts z>6. Their success depends crucially on understanding the character of the reionization process and its observable consequences and…

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

Detection of individual luminous sources during the reionization epoch and cosmic dawn through their signatures in the HI 21-cm signal is one of the direct approaches to probe the epoch. Here, we summarize our previous works on this and…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-27 Kanan K. Datta , Raghunath Ghara , Suman Majumdar , T. Roy Choudhury , Somnath Bharadwaj , Himadri Roy , Abhirup Datta

Context. The increased detection rate of Fast Radio Bursts (FRBs) makes it likely to get samples of sizes $\mathcal{O}(10^2)$ to $\mathcal{O}(10^3)$ in the near future. Because of their extragalactic origin can help us in understanding the…

High Energy Astrophysical Phenomena · Physics 2021-05-28 Albert Wai Kit Lau , Ayan Mitra , Mehdi Shafiee , George Smoot

Observations in the lowest MWA band between $75-100$ MHz have the potential to constrain the distribution of neutral hydrogen in the intergalactic medium at redshift $\sim 13-17$. Using 15 hours of MWA data, we analyse systematics in this…

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