English
Related papers

Related papers: CosmicWeb-21cm array: A New Radio Observation Arra…

200 papers

The redshifted 21-cm emission by neutral hydrogen offers a unique tool for mapping structure formation in the early universe in three dimensions. Here we provide the first detailed calculation of the 21-cm emission signal during and after…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Anastasia Fialkov , Abraham Loeb

Calibrating out per-antenna signal chain effects is an essential step in analyzing radio interferometric data. For drift-scanning arrays, robustly calibrating the data is especially challenging due to the lack of the ability to track a…

Instrumentation and Methods for Astrophysics · Physics 2026-02-09 Robert Pascua , Jonathan Sievers , Adrian Liu

Precise cosmological measurements are essential for understanding the evolution of the universe and the nature of dark energy. The Five-hundred-meter Aperture Spherical Telescope (FAST), the most sensitive single-dish radio telescope, has…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-23 Jun-Da Pan , Peng-Ju Wu , Guo-Hong Du , Yichao Li , Xin Zhang

The separation of cosmological signal from astrophysical foregrounds is a fundamental challenge for any effort to probe the evolution of neutral hydrogen during the Cosmic Dawn and epoch of reionization (EoR) using the 21 cm hyperfine…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-31 Naomi Orosz , Joshua S. Dillon , Aaron Ewall-Wice , Aaron R. Parsons , Nithyanandan Thyagarajan

The cosmic "Dark Ages" is the period between the last scattering of the Cosmic Microwave Background (CMB) and the appearance of the first luminous sources, spanning redshifts $1100\gtrsim z\gtrsim 30$. The only way to observe this period is…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-15 Willow Smith , Jonathan C. Pober

After reionization, emission in the 21 cm hyperfine transition provides a direct probe of neutral hydrogen distributed in galaxies. Different from galaxy redshift surveys, observation of baryon acoustic oscillations in the cumulative 21 cm…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-14 Xiao-Chun Mao

The redshifted 21 cm signal from neutral hydrogen is a direct probe of the physics of the early universe and has been an important science driver of many present and upcoming radio interferometers. In this study we use a single night of…

The sky-averaged, or global, background of redshifted $21$ cm radiation is expected to be a rich source of information on cosmological reheating and reionizaton. However, measuring the signal is technically challenging: one must extract a…

Instrumentation and Methods for Astrophysics · Physics 2016-08-03 Tejaswi Venumadhav , Tzu-Ching Chang , Olivier Doré , Christopher M. Hirata

A new generation of interferometric instruments is emerging which aim to use intensity mapping of redshifted $21\,$cm radiation to measure the large-scale structure of the Universe at $z\simeq 1-2$ over wide areas of sky. While these…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-16 Martin White , Nikhil Padmanabhan

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

Imaging the Universe during the first hundreds of millions of years remains one of the exciting challenges facing modern cosmology. Observations of the redshifted 21 cm line of atomic hydrogen offer the potential of opening a new window…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Jonathan R. Pritchard , Abraham Loeb

The 21-cm forest offers a powerful cosmological probe of the thermal history and small-scale structure of the intergalactic medium during the Epoch of Reionization (EoR). Its success, however, critically depends on the availability of…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-25 Siyuan Zhang , Qi Niu , Yichao Li , Xin Zhang

The cosmological global (sky-averaged) 21-cm signal is a powerful tool to probe the evolution of the intergalactic medium (IGM) in high-redshift Universe ($z \leq 6$). One of the biggest observational challenges is to remove the foreground…

Instrumentation and Methods for Astrophysics · Physics 2018-11-14 Bang D. Nhan , Richard F. Bradley , Jack O. Burns

Foreground mitigation is critical to all next-generation radio interferometers that target cosmology using the redshifted neutral hydrogen 21 cm emission line. Attempts to remove this foreground emission have led to new analysis techniques…

Instrumentation and Methods for Astrophysics · Physics 2022-11-22 Kalyani Bhopi , Will Tyndall , Pranav Sanghavi , Kevin Bandura , Laura Newburgh , Jason Gallicchio

The redshifted 21 cm line, arising from neutral hydrogen, offers a unique probe into the intergalactic medium and the first stars and galaxies formed in the early universe. However, detecting this signal is a challenging task because of…

Instrumentation and Methods for Astrophysics · Physics 2025-10-09 Shijie Sun , Jiaqin Xu , Minquan Zhou , Shenzhe Xu , Fengquan Wu , Haoran Zhang , Juyong Zhang , Bin Ma , Zhaohui Shang , Xuelei Chen

We present a proposal for the construction and development of a new instrument for radio astronomical observations based on interferometric techniques, that will provide high angular resolution in the 21 cm band, with the intention of…

New low frequency radio telescopes currently being built open up the possibility of observing the 21-cm radiation before the Epoch of Reionization in the future, in particular at redshifts 200 > z > 30, also known as the dark ages. At these…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-03 Rishi Khatri , Benjamin D. Wandelt

I review the potential for observing cosmic reionization using the HI 21cm line of neutral hydrogren. Studies include observations of the evolution of large scale structure of the IGM (density, excitation temperature, and neutral fraction),…

Astrophysics · Physics 2009-11-13 C. L. Carilli

21 cm power spectrum observations have the potential to revolutionize our understanding of the Epoch of Reionization and Dark Energy, but require extraordinarily precise data analysis methods to separate the cosmological signal from the…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-31 Miguel F. Morales , Adam Beardsley , Jonathan Pober , Nichole Barry , Bryna Hazelton , Daniel Jacobs , Ian Sullivan