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Related papers: Cosmic Reionization and the 21-cm signal: Comparis…

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We present an analytic formulation to model the fluctuating component of the HI signal from the epoch of reionization during the phase of partial heating. During this phase, we assume self-ionized regions, whose size distribution can be…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-14 Janakee Raste , Shiv Sethi

A new generation of radio telescopes are currently being built with the goal of tracing the cosmic distribution of atomic hydrogen at redshifts 6-15 through its 21-cm line. The observations will probe the large-scale brightness fluctuations…

Astrophysics · Physics 2009-11-13 Rennan Barkana , Abraham Loeb

The redshifted 21cm line signal from neutral hydrogens is a promising tool to probe the cosmic dawn and the epoch of reionization (EoR). Ongoing and future low-frequency radio experiments are expected to detect its fluctuations, especially…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Hayato Shimabukuro , Shintaro Yoshiura , Keitaro Takahashi , Shuichiro Yokoyama , Kiyotomo Ichiki

By heating the intergalactic medium (IGM) before reionization, X-rays are expected to play a prominent role in the early Universe. The cosmic 21-cm signal from this "Epoch of Heating" (EoH) could serve as a clean probe of high-energy…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-31 Arpan Das , Andrei Mesinger , Andrea Pallottini , Andrea Ferrara , John H. Wise

[Abridged] The spatially averaged global spectrum of the redshifted 21cm line has generated much experimental interest, for it is potentially a direct probe of the Epoch of Reionization and the Dark Ages. Since the cosmological signal here…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-07 Adrian Liu , Jonathan R. Pritchard , Max Tegmark , Abraham Loeb

In this work we present a new hybrid method to simulate the thermal effects of the reionization in cosmological hydrodynamical simulations. The method improves upon the standard approach used in simulations of the intergalactic medium (IGM)…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-11 Jose Oñorbe , F. B. Davies , Z. Lukić , J. F. Hennawi , D. Sorini

A detection of the 21-cm signal power spectrum from the Epoch of Reionization is imminent, thanks to consistent advancements from telescopes such as LOFAR, MWA, and HERA, along with the development of SKA. In light of this progress, it is…

The light of the first astrophysical objects is expected to leave an imprint on the global 21-cm signal as it heats, excites, and ionizes neutral hydrogen. This dependence on early astrophysics introduces significant uncertainties in…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-06 Omer Zvi Katz

Observations of the 21cm line of neutral hydrogen are poised to revolutionize our knowledge of cosmic reionization and the high-redshift population of galaxies. However, harnessing such information requires robust and comprehensive…

Astrophysics of Galaxies · Physics 2023-12-19 Joseph S. W. Lewis , Annalisa Pillepich , Dylan Nelson , Ralf S. Klessen , Simon C. O. Glover

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

Preliminary results are presented from a simple, single-antenna experiment designed to measure the all-sky radio spectrum between 100 and 200 MHz. The system used an internal comparison-switching scheme to reduce non-smooth instrumental…

Astrophysics · Physics 2009-11-13 Judd D. Bowman , Alan E. E. Rogers , Jacqueline N. Hewitt

The 21-cm hyperfine line of neutral hydrogen is a useful tool to probe the conditions of the Universe during the Dark Ages, Cosmic Dawn, and the Epoch of Reionisation. In most of the current calculations, the 21-cm line signals at given…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-23 Jennifer Y. H. Chan , Qin Han , Kinwah Wu , Jason D. McEwen

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…

Observations of the redshifted 21 cm line with upcoming radio telescopes promise to transform our understanding of the cosmic reionization. To unravel the underlying physical process, we investigate the 21 cm structures of three different…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Hidenobu Yajima , Yuexing Li

We propose observations of the molecular gas distribution during the era of reionization. At $z \sim $ 6 to 8, $^{12}$CO$(J=1-0)$ line intensity results in a mean brightness temperature of about 0.5 $\mu$K with rms fluctuations of 0.1…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Yan Gong , Asantha Cooray , Marta B. Silva , Mario G. Santos , Phillip Lubin

Aiming to correctly restore the redshifted 21 cm signals emitted by the neutral hydrogen during the cosmic reionization processes, we re-examine the separation approaches based on the quadratic polynomial fitting technique in frequency…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jingying Wang , Haiguang Xu , Tao An , Junhua Gu , Xueying Guo , Weitian Li , Yu Wang , Chengze Liu , Olivier Martineau-Huynh , Xiang-Ping Wu

We show that the epoch(s) of reionization when the ionization fraction of the universe is about half can be determined by correlating Cosmic Microwave Background (CMB) temperature maps with 21-cm line maps at degree scales ($l\sim 100$).…

Astrophysics · Physics 2009-11-13 Marcelo A. Alvarez , Eiichiro Komatsu , Olivier Doré , Paul R. Shapiro

Recently, the Hydrogen Epoch of Reionization Array (HERA) collaboration has produced the experiment's first upper limits on the power spectrum of 21-cm fluctuations at z~8 and 10. Here, we use several independent theoretical models to infer…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-21 The HERA Collaboration , Zara Abdurashidova , James E. Aguirre , Paul Alexander , Zaki Ali , Yanga Balfour , Rennan Barkana , Adam Beardsley , Gianni Bernardi , Tashalee Billings , Judd Bowman , Richard Bradley , Phillip Bull , Jacob Burba , Steven Carey , Christopher Carilli , Carina Cheng , David DeBoer , Matthew Dexter , Eloy de Lera Acedo , Joshua Dillon , John Ely , Aaron Ewall-Wice , Nicolas Fagnoni , Anastasia Fialkov , Randall Fritz , Steven Furlanetto , Kingsley Gale-Sides , Brian Glendenning , Deepthi Gorthi , Bradley Greig , Jasper Grobbelaar , Ziyaad Halday , Bryna Hazelton , Stefan Heimersheim , Jacqueline Hewitt , Jack Hickish , Daniel Jacobs , Austin Julius , Nicholas Kern , Joshua Kerrigan , Piyanat Kittiwisit , Saul Kohn , Matthew Kolopanis , Adam Lanman , Paul La Plante , Telalo Lekalake , David Lewis , Adrian Liu , Yin-Zhe Ma , David MacMahon , Lourence Malan , Cresshim Malgas , Matthys Maree , Zachary Martinot , Eunice Matsetela , Andrei Mesinger , Jordan Mirocha , Mathakane Molewa , Miguel Morales , Tshegofalang Mosiane , Julian Munoz , Steven Murray , Abraham Neben , Bojan Nikolic , Chuneeta Devi Nunhokee , Aaron Parsons , Nipanjana Patra , Samantha Pieterse , Jonathan Pober , Yuxiang Qin , N. Razavi-Ghods , Itamar Reis , Jon Ringuette , James Robnett , Kathryn Rosie , Mario Santos , Sudipta Sikder , Peter Sims , Craig Smith , Angelo Syce , Nithyanandan Thyagarajan , Peter Williams , Haoxuan Zheng

Details of various unknown physical processes during the cosmic dawn and the epoch of reionization can be extracted from observations of the redshifted 21-cm signal. These observations, however, will be affected by the evolution of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-14 Raghunath Ghara , Kanan K. Datta , T. Roy Choudhury

The post-recombination streaming of baryons through dark matter keeps baryons out of low mass (<10^6 solar masses) halos coherently on scales of a few comoving Mpc. It has been argued that this will have a large impact on the 21-cm signal…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-24 Jonathan M. Bittner , Abraham Loeb