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

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The 21-cm hyperfine line of neutral hydrogen is a useful tool to probe the conditions of the Universe during the Dark Ages, Cosmic Dawn, and the Epoch of Reionisation. In most of the current calculations, the 21-cm line signals at given…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-23 Jennifer Y. H. Chan , Qin Han , Kinwah Wu , Jason D. McEwen

Absorption lines at high redshift in front of quasars are rare in the mm domain. Only five associated and five intervening systems have been reported in the literature. These bring very useful information complementary to emission lines,…

Astrophysics of Galaxies · Physics 2023-12-19 Francoise Combes , Neeraj Gupta

In this paper, we explore how the forthcoming generation of large-scale radio continuum surveys, with the inclusion of some degree of redshift information, can constrain cosmological parameters. By cross-matching these radio surveys with…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Stefano Camera , Mário G. Santos , David J. Bacon , Matt J. Jarvis , Kim McAlpine , Ray P. Norris , Alvise Raccanelli , Huub Röttgering

Detecting and studying objects at the highest redshifts, out to the end of Cosmic Reionization at z>7, is clearly a key science goal of ALMA. ALMA will in principle be able to detect objects in this redshift range both from high-J (J>7) CO…

Astrophysics · Physics 2009-06-23 Fabian Walter , Chris Carilli

21 cm cosmology, the statistical observation of the high redshift universe using the hyperfine transition of neutral hydrogen, has the potential to revolutionize our understanding of cosmology and the astrophysical processes that underlie…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-10 Joshua S. Dillon

Redshifted 21 cm radiation originating from the cosmological distribution of neutral hydrogen (HI) appears as a background radiation in low frequency radio observations. The angular and frequency domain fluctuations in this radiation carry…

Astrophysics · Physics 2007-05-23 Somnath Bharadwaj , SK. Saiyad Ali

The statistical uncertainty in measuring the primordial density perturbations on a given comoving scale is dictated by the number of independent regions of that scale that are accessible to an observer. This number varies with cosmic time…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Abraham Loeb

Abridged: The golden age of astrophysics is upon us with both grand discoveries (extra-solar planets, dark matter, dark energy) and precision cosmology. Fundamental understanding of the working of stars and galaxies is within reach, thanks…

Morphology of the complex HI gas distribution can be quantified by statistics like the Minkowski functionals, and can provide a way to statistically study the large scale structure in the HI maps both at low redshifts, and during the epoch…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-19 Yougang Wang , Yidong Xu , Fengquan Wu , Xuelei Chen , Xin Wang , Juhan Kim , Changbom Park , Khee-Gan Lee , Renyue Cen

The large-scale dynamics of the universe is generally described in terms of the time-dependent scale factor $a(t)$. To make contact with observational data, the $a(t)$ function needs to be related to the observable $z(r)$ function, redshift…

General Physics · Physics 2025-06-17 Jan Stenflo

The extremely high sensitivity and resolution of the Square Kilometre Array (SKA) will be useful for addressing a wide set of themes relevant for cosmology, in synergy with current and future cosmic microwave background (CMB) projects. Many…

The next generation of space-based experiments will go hunting for answers to cosmology's key open questions which revolve around inflation, dark matter and dark energy. Low earth orbit and lunar missions within the European Space Agency's…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-08 Gianfranco Bertone , Oliver L. Buchmueller , Philippa S. Cole

The Square Kilometre Array will be a revolutionary instrument for the study of gas in the distant Universe. SKA1 will have sufficient sensitivity to detect and image atomic 21 cm HI in individual galaxies at significant cosmological…

Astrophysics of Galaxies · Physics 2014-12-19 J. Wagg , E. Da Cunha , C. L. Carilli , F. Walter , M. Aravena , I. Heywood , J. Hodge , E. Murphy , D. Riechers , M. Sargent , R. Wang

I discuss the implications of the Parkes HI Multibeam Southern Sky Survey for cosmology. It will determine the local mass function of HI clouds, detecting several hundred per decade of mass. Each of these will come with a redshift and, for…

Astrophysics · Physics 2007-05-23 P. A. Thomas

Imaging surveys will find many tens to hundreds of thousands of Type Ia supernovae in the next decade, and measure their light curves. In addition to a need for characterizing their types and subtypes, a redshift is required to place them…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-04 Eric V. Linder , Ayan Mitra

A huge amount of good quality data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision Cosmology. Despite…

General Relativity and Quantum Cosmology · Physics 2008-12-02 S. Capozziello

Line-intensity mapping (LIM) is an emerging approach to survey the Universe, using relatively low-aperture instruments to scan large portions of the sky and collect the total spectral-line emission from galaxies and the intergalactic…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-01 José Luis Bernal , Ely D. Kovetz

Recently collected SNIa data have been used to address the problem of measuring the cosmological parameters of the universe. Analysed in the framework of homogeneous models, they have yielded, as a primary result, a strictly positive…

Astrophysics · Physics 2007-05-23 Marie-Noëlle Célérier

Strong evidence has recently emerged for a variation in the fine structure constant, $\alpha\equiv e^2/\hbar c$, over the history of the Universe. This was concluded from a detailed study of the relative positions of redshifted optical…

Astrophysics · Physics 2009-11-10 S. J. Curran , N. Kanekar , J. K. Darling

Supernovae play a large but poorly understood role in our attempts to explain the evolution of the baryonic universe. Numerous observations throughout astronomy cannot be explained if we neglect their influence, yet our quantitative…

Astrophysics · Physics 2007-05-23 K. L. Adelberger