English
Related papers

Related papers: Global CD/EoR Signal Detection with a Dense Digita…

200 papers

Efforts are being made to observe the 21-cm signal from the 'cosmic dawn' using sky-averaged observations with individual radio dipoles. In this paper, we develop a model of the observations accounting for the 21-cm signal, foregrounds, and…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-26 Geraint J. A. Harker , Jonathan R. Pritchard , Jack O. Burns , Judd D. Bowman

The Epoch of Reionisation (EoR) is the period within which the neutral universe transitioned to an ionised one. This period remains unobserved using low-frequency radio interferometers which target the 21 cm signal of neutral hydrogen…

Instrumentation and Methods for Astrophysics · Physics 2021-07-01 J. Kariuki Chege , C. H. Jordan , C. Lynch , J. L. B. Line , C. M. Trott

Interferometry of the cosmic 21-cm signal is set to revolutionise our understanding of the Epoch of Reionisation (EoR) and the Cosmic Dawn (CD). The culmination of ongoing efforts will be the upcoming Square Kilometre Array (SKA), which…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Bradley Greig , Andrei Mesinger , Léon V. E. Koopmans

For there to be a successful measurement of the 21 cm Epoch of Reionization (EoR) power spectrum, it is crucial that strong foreground contaminants be robustly suppressed. These foregrounds come from a variety of sources (such as Galactic…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-25 Adrian Liu , Aaron R. Parsons , Cathryn M. Trott

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

Radio antennas have become a standard tool for the detection of cosmic-ray air showers in the energy range above $10^{16}\,$eV. The radio signal of these air showers is generated mostly due to the deflection of electrons and positrons in…

High Energy Astrophysical Phenomena · Physics 2025-10-28 Frank G. Schröder

The 21 cm hyperfine transition of neutral hydrogen offers a promising probe of the large scale structure of the universe before and during the Epoch of Reionization, when the first ionizing sources formed. Bright radio emission from…

Instrumentation and Methods for Astrophysics · Physics 2020-04-22 Adam E. Lanman , Jonathan C. Pober , Nicholas S. Kern , Eloy de Lera Acedo , David R. DeBoer , Nicolas Fagnoni

The ionosphere introduces chromatic distortions on low frequency radio waves, and thus poses a hurdle for 21-cm cosmology. In this paper we introduce time-varying chromatic ionospheric effects on simulated antenna temperature data of a…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 Emma Shen , Dominic Anstey , Eloy de Lera Acedo , Anastasia Fialkov

The sky-averaged (global) highly redshifted 21-cm spectrum from neutral hydrogen is expected to appear in the VHF range of $\sim20-200$ MHz and its spectral shape and strength are determined by the heating properties of the first stars and…

Instrumentation and Methods for Astrophysics · Physics 2018-10-24 Keith Tauscher , David Rapetti , Jack O. Burns , Eric R. Switzer

We propose a deep learning analyzing technique with convolutional neural network (CNN) to predict the evolutionary track of the Epoch of Reionization (EoR) from the 21-cm differential brightness temperature tomography images. We use…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-15 Yungi Kwon , Sungwook E. Hong , Inkyu Park

With the development of astronomical facilities, large-scale time series data observed by these facilities is being collected. Analyzing anomalies in these astronomical observations is crucial for uncovering potential celestial events and…

Machine Learning · Computer Science 2024-03-18 Xinli Hao , Yile Chen , Chen Yang , Zhihui Du , Chaohong Ma , Chao Wu , Xiaofeng Meng

We revisit the global 21cm signal calculation incorporating a possible radio background at early times, and find that the global 21cm signal shows a much stronger absorption feature, which could enhance detection prospects for future 21 cm…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Chang Feng , Gilbert Holder

Observations of the EoR with the 21-cm hyperfine emission of neutral hydrogen (HI) promise to open an entirely new window onto the formation of the first stars, galaxies and accreting black holes. In order to characterize the weak 21-cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 Abhik Ghosh , L. V. E. Koopmans , Emma Chapman , Vibor Jelic

The Hydrogen Epoch of Reionization Array (HERA) is a radio interferometer aiming to detect the power spectrum of 21 cm fluctuations from neutral hydrogen from the Epoch of Reionization (EOR). Drawing on lessons from the Murchison Widefield…

The redshifted 21cm line of neutral hydrogen (HI), potentially observable at low radio frequencies (~50-200 MHz), should be a powerful probe of the physical conditions of the inter-galactic medium during Cosmic Dawn and the Epoch of…

The search for the spectral signature of hydrogen from the formation of the first stars, known as Cosmic Dawn or First Light, is an ongoing effort around the world. The signature should present itself as a decrease in the temperature of the…

Instrumentation and Methods for Astrophysics · Physics 2021-12-30 Christopher DiLullo , Gregory B. Taylor , Jayce Dowell

The measurements of the 21-cm brightness temperature fluctuations from the neutral hydrogen at the Epoch of Reionization (EoR) should inaugurate the next generation of cosmological observables. In this respect, many works have concentrated…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-10 Sebastien Clesse , Laura Lopez-Honorez , Christophe Ringeval , Hiroyuki Tashiro , Michel H. G. Tytgat
‹ Prev 1 3 4 5 6 7 10 Next ›