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Related papers: HI and Cosmology: What We Need To Know

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Line-Intensity Mapping (LIM) has emerged as a powerful technique for studying large-scale structure and the high-redshift universe, enabling three-dimensional maps of line emission across vast cosmological volumes. In this review, we…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-04 Tzu-Ching Chang , Adam Lidz

The SKA and its pathfinders will enable studies of HI emission at higher redshifts than ever before. In moving beyond the local Universe, this will require the use of cosmologically appropriate formulae that have traditionally been…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-14 Martin Meyer , Aaron Robotham , Danail Obreschkow , Tobias Westmeier , Alan Duffy , Lister Staveley-Smith

The SKA will build upon early detections of the EoR by precursor instruments, such as MWA, PAPER, and LOFAR, and planned instruments, such as HERA, to make the first high signal-to-noise measurements of fluctuations in the 21 cm brightness…

Galaxy redshift surveys are a major tool to address the most challenging cosmological problems facing cosmology, like the nature of dark energy and properties dark matter. The same observations are useful for a much larger variety of…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-10 Laerte Sodre

We study the constraints which the next generation of radio telescopes could place on the nature of dark energy, dark matter and inflation by studying the gravitational lensing of high redshift 21 cm emission, and we compare with the…

Astrophysics · Physics 2009-06-23 R. Benton Metcalf , S. D. M. White

We present a framework for forecasting cosmological constraints from future neutral hydrogen intensity mapping experiments at low to intermediate redshifts. In the process, we establish a simple way of comparing such surveys with optical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-08 Philip Bull , Pedro G. Ferreira , Prina Patel , Mario G. Santos

We briefly review the beginnings of HI astronomy, proceed to an assessment of our current capabilities in this area, and continue by considering what will be necessary to push back the frontier to cosmological distances. We then consider…

Astrophysics · Physics 2016-01-27 Robert Braun

In this white paper, we lay out a US roadmap for high-redshift 21 cm cosmology (30 < z < 6) in the 2020s. Beginning with the currently-funded HERA and MWA Phase II projects and advancing through the decade with a coordinated program of…

The cosmic dark ages and the epoch of reionization, during which the first generations of stars and galaxies formed, are among the most compelling frontiers of extragalactic astrophysics and cosmology. Here we describe an exciting new probe…

Galaxy redshift surveys using optical telescopes have, in combination with other cosmological probes, enabled precision measurements of the nature of dark energy. We show that radio telescopes are rapidly becoming competitive with optical…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-07 Alan R. Duffy

Hydrogen, the most abundant element in the Universe, has traditionally been used to investigate astrophysical processes within and around our own Galaxy. In its chemically neutral, atomic form (known as HI in the astronomical literature),…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-14 Hamsa Padmanabhan

The new frontier of cosmology will be led by three-dimensional surveys of the large-scale structure of the Universe. Based on its all-sky surveys and redshift depth, the SKA is destined to revolutionize cosmology, in combination with future…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-14 Roy Maartens , Filipe B. Abdalla , Matt Jarvis , Mario G. Santos

We have had the chance to live through a fascinating revolution in measuring the fundamental empirical cosmological Hubble law. The key progress is analysed : 1) improvement of observational means (ground-based radio and optical…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-10 Georges Paturel , Pekka Teerikorpi , Yurij Baryshev

The Square Kilometer Array (SKA) has the potential to produce galaxy redshift surveys which will be competitive with other state of the art cosmological experiments in the next decade. In this chapter we summarise what capabilities the…

Redshift drift provides a direct kinematic measurement of cosmic acceleration but it occurs with a characteristic time scale of a Hubble time. Thus redshift observations with a challenging precision of $10^{-9}$ require a 10 year time span…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-01 Alex G. Kim , Eric V. Linder , Jerry Edelstein , David Erskine

The Square Kilometre Array (SKA) will have a low frequency component (SKA-low) which has as one of its main science goals the study of the redshifted 21cm line from the earliest phases of star and galaxy formation in the Universe. This 21cm…

SKA is a new technology radio-telescope array, about two orders of magnitude more sensitive and rapid in sky surveys than present instruments. It will probe the dark age of the universe, just afer recombination, and during the epoch of…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 Francoise Combes

The emission of 21-cm radiation from a neutral intergalactic medium (IGM) at high redshift is discussed in connection with the thermal and ionization history of the universe. The physical mechanisms that make such radiation detectable…

Astrophysics · Physics 2009-10-31 Paolo Tozzi , Piero Madau , Avery Meiksin , Martin J. Rees

This review discusses three ways in which radio galaxies and other high-redshift objects can give us information on the nature and statistics of cosmological inhomogeneities, and how they have evolved between high redshift and the present:…

Astrophysics · Physics 2007-05-23 J. A. Peacock