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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 cosmic 21-cm signal is a promising probe of the early Universe, owing to its sensitivity to the thermal state of the neutral intergalactic medium (IGM) and properties of the first luminous sources. Here, we constrain the 21-cm signal…

The 21-cm signal from the Epoch of Reionization (EoR) is a powerful probe of the evolution of the Universe. However, accurate measurements of the EoR signal from radio interferometric observations are sensitive to efficient foreground…

Instrumentation and Methods for Astrophysics · Physics 2025-09-23 Madhurima Choudhury , Jonathan C. Pober

We present here 21 cm predictions from high dynamic range simulations for a range of reionization histories that have been tested against available Lyman-alpha and CMB data. We assess the observability of the predicted spatial 21 cm…

Astrophysics of Galaxies · Physics 2016-09-13 Girish Kulkarni , Tirthankar Roy Choudhury , Ewald Puchwein , Martin G. Haehnelt

The future 21 cm intensity mapping observations constitute a promising way to trace the matter distribution of the Universe and probe cosmology. Here we assess its capability for cosmological constraints using as a case study the BINGO…

We extend 21CMMC, a Monte Carlo Markov Chain sampler of 3D reionisation simulations, to perform parameter estimation directly on 3D light-cones of the cosmic 21cm signal. This brings theoretical analysis closer to the tomographic 21-cm…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-11 Bradley Greig , Andrei Mesinger

The 21cm line probes the evolution of matter perturbations over a wide range of redshifts, from the dark ages down to the completion of reionization. Observing the 21cm cosmological signal will extend our understanding of the evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-26 Xue-Wen Liu , Caroline Heneka , Luca Amendola

The 21-cm signal of neutral hydrogen is a sensitive probe of the Epoch of Reionization (EoR) and Cosmic Dawn. Currently operating radio telescopes have ushered in a data-driven era of 21-cm cosmology, providing the first constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-10 Aviad Cohen , Anastasia Fialkov , Rennan Barkana , Raul Monsalve

The 21-cm absorption feature reported by the EDGES collaboration is several times stronger than that predicted by traditional astrophysical models. If genuine, a deeper absorption may lead to stronger fluctuations on the 21-cm signal on…

Models of the reionization and reheating of the intergalactic medium (IGM) at redshifts $z \gtrsim 6$ continue to grow more sophisticated in anticipation of near-future 21-cm, cosmic microwave background, and galaxy survey measurements.…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-11 Jordan Mirocha , Henri Lamarre , Adrian Liu

The EDGES collaboration has reported the detection of a global 21-cm signal with a plateau centered at 76 MHz (i.e., redshift 17.2), with an amplitude of 500^(+200)_(-500) mK. This anomalous measurement does not comport with standard…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-22 Fulvio Melia

The extraction of the sky-averaged 21 cm signal from Cosmic Dawn and the Epoch of Reionization faces significant challenges. The bright and anisotropic Galactic foreground, which is 4 - 5 orders of magnitude brighter than the 21 cm signal,…

Instrumentation and Methods for Astrophysics · Physics 2025-12-10 Haoran Li , Furen Deng , Meng Zhou , Yidong Xu , Xuelei Chen

The response of the antenna is a source of uncertainty in measurements with the Experiment to Detect the Global EoR Signature (EDGES). We aim to validate the beam model of the low-band (50-100 MHz) dipole antenna with comparisons between…

Instrumentation and Methods for Astrophysics · Physics 2021-07-07 Nivedita Mahesh , Judd D. Bowman , Thomas J. Mozdzen , Alan E. E. Rogers , Raul A. Monsalve , Steven G. Murray , David Lewis

The Epoch of Reionization (EoR) and Cosmic Dawn (CD) are pivotal stages during the first billion years of the universe, exerting a significant influence on the development of cosmic structure. The detection of the redshifted 21-cm signal…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-14 Anshuman Tripathi , Abhirup Datta , Aishrila Mazumder , Suman Majumdar

With a statistical detection of the 21 cm signal fluctuations from the Epoch of Reionization (EoR) expected in the next few years, there is an interest in developing robust and precise techniques to constrain the underlying astrophysical…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-25 Evan Eames , Aristide Doussot , Benoît Semelin

A detection of the 21 cm signal can provide a unique window of opportunity for uncovering complex astrophysical phenomena at the epoch of reionization and placing constraints on cosmology at high redshifts, which are usually elusive to…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-21 Danial Baradaran , Boryana Hadzhiyska , Martin J. White , Noah Sailer

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

The HI 21cm absorption line is masked by bright foregrounds and systematic distortions that arise due to the chromaticity of the antenna used to make the observation coupling to the spectral inhomogeneity of these foregrounds. We…

Instrumentation and Methods for Astrophysics · Physics 2021-11-12 Dominic Anstey , Eloy de Lera Acedo , Will Handley

A novel wireless transmission scheme, as named the reconfigurable intelligent surface (RIS)-assisted received adaptive spatial modulation (RASM) scheme, is proposed in this paper. In this scheme, the adaptive spatial modulation (ASM)-based…

Information Theory · Computer Science 2025-02-26 Chaorong Zhang , Hui Xu , Benjamin K. Ng , Chan-Tong Lam , Ke Wang

Detecting the cosmic 21-cm signal during the Epoch of Reionisation and Cosmic Dawn will reveal insights into the properties of the first galaxies and advance cosmological parameter estimation. Until recently, the primary focus for…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Bradley Greig , Yuan-Sen Ting , Alexander A. Kaurov