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Related papers: Hydrogen Epoch of Reionization Array (HERA)

200 papers

Neutral hydrogen (HI) serves as a crucial probe for the Cosmic Dawn and the Epoch of Reionization (EoR). Actual observations of the 21-cm signal often encounter challenges such as thermal noise and various systematic effects. To overcome…

The recent low value of Planck (2016) integrated optical depth to Thomson scattering suggests that the reionization occurred fairly suddenly, disfavoring extended reionization scenarios. This will have a significant impact on the 21cm power…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-27 Sultan Hassan , Romeel Dave , Kristian Finlator , Mario G. Santos

The global 21 cm signal from Cosmic Dawn (CD) and the Epoch of Reionization (EoR), at redshifts $z \sim 6-30$, probes the nature of first sources of radiation as well as physics of the Inter-Galactic Medium (IGM). Given that the signal is…

Instrumentation and Methods for Astrophysics · Physics 2018-04-25 Saurabh Singh , Ravi Subrahmanyan , N. Udaya Shankar , Mayuri Sathyanarayana Rao , B. S. Girish , A. Raghunathan , R. Somashekar , K. S. Srivani

A first statistical detection of the 21-cm Epoch of Reionization (EoR) is on the horizon, as cosmological volumes of the Universe become accessible via the adoption of low-frequency interferometers. We explore the impact which non-identical…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-01 A. Chokshi , N. Barry , J. L. B. Line , C. H. Jordan , B. Pindor , R. L. Webster

Upcoming 21cm surveys with the SKA1-LOW telescope will enable imaging of the neutral hydrogen distribution on cosmological scales in the early Universe. These surveys are expected to generate huge imaging datasets that will encode more…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-22 Tumelo Mangena , Sultan Hassan , Mario G. Santos

The redshifted 21cm signal from Cosmic Dawn promises to open a new window into the early history of our universe and enable the probing of an unprecedented comoving survey volume. In this work, we revisit the imprint of Warm Dark Matter…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-16 Quentin Decant , Androniki Dimitriou , Laura Lopez Honorez , Bryan Zaldivar

The MeerKAT (64 x 13.5m dish radio interferometer) is South Africa's precursor instrument for the Square Kilometre Array (SKA), exploring dish design, instrumentation, and the characteristics of a Karoo desert site and is projected to be on…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 B. W. Holwerda , S. --L. Blyth , A. J. Baker , the LADUMA team

The epoch of reionization (EoR) marks the last phase transition of hydrogen in our Universe, as it evolves from cold and neutral to hot and ionized in the intergalactic medium (IGM). While its endpoint and duration can be estimated from…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-12 Sarah Libanore , Ely D. Kovetz , Julian B. Munoz , Yonatan Sklansky , Emilie Thélie

Distribution of cold gas in the post-reionization era provides an important link between distribution of galaxies and the process of star formation. Redshifted 21 cm radiation from the Hyperfine transition of neutral Hydrogen allows us to…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Bharat Kumar Gehlot , Jasjeet Singh Bagla

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

The cosmic 21-cm line of hydrogen is expected to be measured in detail by the next generation of radio telescopes. The enormous dataset from future 21-cm surveys will revolutionize our understanding of early cosmic times. We present a…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-11 Sudipta Sikder , Rennan Barkana , Itamar Reis , Anastasia Fialkov

We introduce 21CMMC: a parallelized, Monte Carlo Markov Chain analysis tool, incorporating the epoch of reionization (EoR) seminumerical simulation 21CMFAST. 21CMMC estimates astrophysical parameter constraints from 21 cm EoR experiments,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Bradley Greig , Andrei Mesinger

We describe the design and performance of the Engineering Development Array (EDA), which is a low frequency radio telescope comprising 256 dual-polarisation dipole antennas working as a phased-array. The EDA was conceived of, developed, and…

Observations of the frequency dependence of the global brightness temperature of the redshifted 21 cm line of neutral hydrogen may be possible with single dipole experiments. In this paper, we develop a Fisher matrix formalism for…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Jonathan R. Pritchard , Abraham Loeb

The first generation of redshifted 21 cm detection experiments, carried out with arrays like LOFAR, MWA and GMRT, will have a very low signal-to-noise ratio per resolution element (\sim 0.2). In addition, whereas the variance of the…

Upcoming galaxy surveys with the SKA Observatory will detect neutral hydrogen (HI) across unprecedented volumes, and their scientific return will crucially depend on predictive models for HI observables. In this work, we present a framework…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-25 Joël Mayor , Marta Spinelli , Gabriella De Lucia , Robert Yates , Alexandre Refregier , Fabio Fontanot , Lizhi Xie , Michaela Hirschmann

Prior to the epoch of full reionization, the intergalactic medium and gravitationally collapsed systems will be detectable in 21-cm radiation. Physical mechanisms that would produce a 21-cm signature are discussed. These include Lya…

Astrophysics · Physics 2007-05-23 A Meiksin

The low-frequency component of the upcoming Square Kilometre Array Observatory (SKA-Low) will be sensitive enough to construct 3D tomographic images of the 21-cm signal distribution during reionisation. However, foreground contamination…

The epoch of reionization (EoR), marking the Universe's transition from a neutral to ionized state, represents a pivotal phase for understanding the formation of the first stars and galaxies. Intensity mapping of atomic and molecular lines,…

Astrophysics of Galaxies · Physics 2025-12-17 Anirban Roy , Anthony Pullen , Patrick C. Breysse , Rachel S. Somerville

The 21-cm power spectrum of reionization is a promising probe for cosmology and fundamental physics. Exploiting this new observable, however, requires fast predictors capable of efficiently scanning the very large parameter space of…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Aurel Schneider , Timothée Schaeffer , Sambit K. Giri