English
Related papers

Related papers: The large-scale 21-cm power spectrum from reioniza…

200 papers

We present upper limits on the 21 cm power spectrum at $z = 5.9$ calculated from the model-independent limit on the neutral fraction of the intergalactic medium of $x_{\rm H{\small I }} < 0.06 + 0.05\ (1\sigma)$ derived from dark pixel…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Jonathan C. Pober , Bradley Greig , Andrei Mesinger

Detection and analysis of the cosmic 21 cm signal of neutral hydrogen has long been considered the most promising route towards exploration of the Epoch of Reionization (EoR). 21CMMC, a Markov Chain Monte Carlo sampler of the semi-numerical…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-19 August Berklas , Jonathan Pober

Mapping of the neutral hydrogen (HI) 21-cm intensity fluctuations across redshifts promises a novel and powerful probe of cosmology. The neutral hydrogen gas mass density, $\Omega_{\rm HI}$ and bias parameter, $b_{\rm HI}$ are key…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-10 Hamsa Padmanabhan , T. Roy Choudhury , Alexandre Refregier

Cross-correlations between 21cm observations and galaxy surveys provide a powerful probe of reionization by reducing foreground sensitivity while linking ionization morphology to galaxies. We quantify the constraining power of 21cm-Galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Yannic Pietschke , Anne Hutter , Caroline Heneka

The redshifted 21-cm signal from neutral hydrogen (HI) in the intergalactic medium (IGM) is a powerful probe of the Epoch of Reionization (EoR). Owing to the complex growth and morphology of ionized regions, the 21-cm brightness-temperature…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 Vishrut Pandya , Leon Noble , Suman Majumdar , Debanjan Sarkar , Mohd Kamran , Abhirup Datta

Combining the visibilities measured by an interferometer to form a cosmological power spectrum is a complicated process. In a delay-based analysis, the mapping between instrumental and cosmological space is not a one-to-one relation.…

The potential use of the redshifted 21 cm line from neutral hydrogen for probing the epoch of reionization is motivating the construction of several low-frequency interferometers. There is also much interest in the possibility of…

Astrophysics · Physics 2008-12-18 Jonathan R. Pritchard , Abraham Loeb

The mean free path of ionizing photons ($\lambda_\mathrm{mfp}^{912}$) in the intergalactic medium (IGM) is a crucial quantity in modelling the ionization state of IGM and the extragalactic ultraviolet background (EUVB), and is widely used…

Observations of the neutral Hydrogen (\HI ) 21-cm signal hold the potential of allowing us to map out the cosmological large scale structures (LSS) across the entire post-reionization era ($z \leq 6$). Several experiments are planned to map…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-11 Debanjan Sarkar , Somnath Bharadwaj , Anathpindika S.

The redshifted 21-cm signal is a unique probe of the early universe, particularly the Epoch of Reionization (EoR). While the 21-cm power spectrum has been the primary statistic for parameter inference, it fails to capture the non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-03 Anoop Krishna , Deepthi Moorkanat , Hiten , Rajesh Mondal

The 21-cm forest, composed of spectral absorption features from high-redshift background radio sources, provides a unique probe for studying small-scale structures during the epoch of reionization. It is particularly sensitive to detecting…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-11 Yue Shao , Tian-Yang Sun , Meng-Lin Zhao , Xin Zhang

Measurements of the Epoch of Reionization (EoR) 21-cm signal hold the potential to constrain models of reionization. In this paper we consider a reionization model with three astrophysical parameters namely (1) the minimum halo mass which…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-18 Abinash Kumar Shaw , Somnath Bharadwaj , Rajesh Mondal

The cosmic microwave background (CMB) polarisation and the 21 cm line fluctuations are powerful probes of cosmological reionisation. We study how the cross-correlation between the CMB polarisation (E-modes) and the 21 cm line fluctuations…

Astrophysics · Physics 2009-04-17 Hiroyuki Tashiro , Nabila Aghanim , Mathieu Langer , Marian Douspis , Saleem Zaroubi

In order to study the "Cosmic Dawn" and the Epoch of Reionization with 21 cm tomography, we need to statistically separate the cosmological signal from foregrounds known to be orders of magnitude brighter. Over the last few years, we have…

In the absence of complex astrophysical processes that characterize the reionization era, the 21-cm emission from neutral hydrogen (HI) in the post-reionization epoch is believed to be an excellent tracer of the underlying dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Tapomoy Guha Sarkar , Sourav Mitra , Suman Majumdar , Tirthankar Roy Choudhury

The amplitude of redshifted 21 cm fluctuations during the Epoch of Reionization (EoR) is expected to show a distinctive "rise and fall" behavior with decreasing redshift as reionization proceeds. On large scales (k <~ 0.1 Mpc^{-1}) this can…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-06 Angus Beane , Adam Lidz

Preparing for the first detection of the cosmic 21-cm signal from large-scale interferometer experiments requires rigorous testing of the data analysis and reduction pipelines. To validate that these pipelines do not erroneously remove or…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-14 Bradley Greig , J. Stuart B. Wyithe , Steven G. Murray , Simon J. Mutch , Cathryn M. Trott

We study the viability of using power spectrum clustering wedges as summary statistics of 21cm surveys during the Epoch of Reionization (EoR). For observations in a wide redshift range $z\sim 7-9$ corresponding to a line-of-sight scale of…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-31 Zhaoting Chen , Alkistis Pourtsidou

The 21-cm line of hydrogen is the most promising probe of the Dark Ages and Cosmic Dawn. We combine hydrodynamical simulations with a large-scale grid in order to calculate the effect of non-linear structure formation on the large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-24 Sudipta Sikder , Hyunbae Park , Rennan Barkana , Naoki Yoshida , Anastasia Fialkov