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Related papers: De-contamination of cosmological 21-cm maps

200 papers

Observation of the redshifted 21-cm signal from Cosmic Dawn and Epoch of Reionization is a challenging endeavor in observational cosmology. Presence of orders of magnitude brighter astrophysical foregrounds and various instrumental…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-03 Aishrila Mazumder , Abhirup Datta , Arnab Chakraborty , Suman Majumdar

We use numerical simulations of hydrogen reionization by stellar sources in the context of LCDM cosmogonies to investigate the 21 (1+z) cm radio signal expected from the diffuse intergalactic medium (IGM) prior to the epoch of reionization…

Astrophysics · Physics 2009-07-09 B. Ciardi , P. Madau

Interferometry of the cosmic 21-cm signal is set to revolutionize our understanding of the Epoch of Reionization (EoR), eventually providing 3D maps of the early Universe. Initial detections however will be low signal-to-noise, limited by…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-20 Emanuele Sobacchi , Andrei Mesinger , Bradley Greig

Modern machine learning will allow for simulation-based inference from reionization-era 21cm observations at the Square Kilometre Array. Our framework combines a convolutional summary network and a conditional invertible network through a…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-16 Benedikt Schosser , Caroline Heneka , Tilman Plehn

We explore the impact of dark matter annihilation on the 21-cm signal during the cosmic dawn and epoch of reionization (EoR). Using modified 21cmFAST simulations and convolutional neural networks (CNNs), we investigate how energy injected…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-10 Atsushi J. Nishizawa , Pravin Kumar Natwariya , Kenji Kadota

We consider the effectiveness of foreground cleaning in the recovery of Cosmic Microwave Background (CMB) polarization sourced by gravitational waves for tensor-to-scalar ratios in the range $0<r<0.1$. Using the planned survey area,…

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 properties of the first galaxies, expected to drive the Cosmic Dawn (CD) and the Epoch of Reionization (EoR), are encoded in the 3D structure of the cosmic 21-cm signal. Parameter inference from upcoming 21-cm observations promises to…

Astrophysics of Galaxies · Physics 2019-01-24 Jaehong Park , Andrei Mesinger , Bradley Greig , Nicolas Gillet

Current and upcoming radio interferometric experiments are aiming to make a statistical characterization of the high-redshift 21cm fluctuation signal spanning the hydrogen reionization and X-ray heating epochs of the universe. However,…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-19 Nicholas S. Kern , Adrian Liu , Aaron R. Parsons , Andrei Mesinger , Bradley Greig

A new method for removing point radio sources and other non-Gaussian noise is proposed as a means of improving the accuracy of estimates of the angular power spectrum of the cosmic microwave background (CMB). The main idea of the method is…

Astrophysics · Physics 2009-11-13 Anisa T. Bajkova

Spatial variations in the Lyman-$\alpha$ forest opacity at $z<6$ seem to require a late end to cosmic reionization. In this picture, the universe contains neutral hydrogen 'islands' of up to 100 cMpc$/h$ in extent down to redshifts as low…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-06 Janakee Raste , Girish Kulkarni , Catherine A. Watkinson , Laura C. Keating , Martin G. Haehnelt

Using a combination of N-body simulations, semi-analytic models and radiative transfer calculations, we have estimated the theoretical cross power spectrum between galaxies and the 21cm emission from neutral hydrogen during the epoch of…

We present a Markov Chain Monte Carlo (MCMC)-based parameter estimation package, CosmoReionMC, to jointly constrain cosmological parameters of the $\Lambda$CDM model and the astrophysical parameters related to hydrogen reionization. The…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-18 Atrideb Chatterjee , Tirthankar Roy Choudhury , Sourav Mitra

21 cm cosmology is a promising new probe of the evolution of visible matter in our universe, especially during the poorly-constrained Cosmic Dawn and Epoch of Reionization. However, in order to separate the 21 cm signal from bright…

We investigate the potential of second generation measurements of redshifted 21 cm radiation from before and during the epoch of reionization (EOR) to reconstruct the matter density fluctuations along the line of sight. To do so we…

Astrophysics · Physics 2008-11-26 Oliver Zahn , Matias Zaldarriaga

The birth of the first luminous sources and the ensuing epoch of reionization are best studied via the redshifted 21-cm emission line, the signature of the first two imprinting the last. In this work we present a fully-Bayesian method,…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-27 G. Bernardi , J. T. L. Zwart , D. Price , L. J. Greenhill , A. Mesinger , J. Dowell , T. Eftekhari , S. W. Ellingson , J. Kocz , F. Schinzel

Mapping the distribution of neutral atomic hydrogen (HI) in the Universe through its 21 cm emission line provides a powerful cosmological probe to map the large-scale structures and shed light on various cosmological phenomena. The Baryon…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-20 Albin Joseph , Rajib Saha

We present the first large-scale radiative transfer simulations of cosmic reionization, in a simulation volume of (100/h Mpc)^3, while at the same time capturing the dwarf galaxies which are primarily responsible for reionization. We…

Currently several low-frequency experiments are being planned to study the nature of the first stars using the redshifted 21-cm signal from the cosmic dawn and epoch of reionization. Using a one-dimensional radiative transfer code, we model…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-13 Raghunath Ghara , T. Roy Choudhury , Kanan K. Datta

We examine the possibility of constraining the cosmological mean mass and dark energy densities by an application of the Alcock-Paczynski test on redshifted 21-cm maps of the epoch of reionization. The 21-cm data will be provided as a…

Astrophysics · Physics 2009-11-10 Adi Nusser
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