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Related papers: Forecasts on Primordial non-Gaussianity from 21 cm…

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Potential evidence for primordial non-Gaussianity (PNG) is expected to lie in the largest scales mapped by cosmological surveys. Forthcoming 21cm intensity mapping experiments will aim to probe these scales by surveying neutral hydrogen…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-20 Steven Cunnington , Stefano Camera , Alkistis Pourtsidou

The primordial non-Gaussianity induces scale-dependent bias of the \hi with respect to the underlying dark matter, which exhibits features on the very large scales of the 21-cm power spectrum potentially observable with \hi intensity…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-04 Yi-Chao Li , Yin-Zhe Ma

The large-scale structure of the Universe supplies crucial information about the physical processes at play at early times. Unresolved maps of the intensity of 21 cm emission from neutral hydrogen HI at redshifts z~1-5 are the best hope of…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-28 Stefano Camera , Mario G. Santos , Pedro G. Ferreira , Luis Ferramacho

Mapping the unresolved intensity of the 21-cm emission of neutral hydrogen (HI) is now regarded as one the most promising tools for cosmological investigation in the coming decades. Here, we investigate, for the first time, extensions of…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-05 Stefano Camera , Hamsa Padmanabhan

After reionisation, the 21cm emission line of neutral hydrogen within galaxies provides a tracer of dark matter. Next-generation intensity mapping surveys, with the SKA and other radio telescopes, will cover large sky areas and a wide range…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-07 Dionysios Karagiannis , José Fonseca , Roy Maartens , Stefano Camera

\textsc{Hi} intensity mapping will provide maps of the large-scale distribution of neutral hydrogen (\textsc{Hi}) in the universe. These are prime candidates to be used to constrain primordial non-Gaussianity using the Large Scale Structure…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-03 José Fonseca , Michele Liguori

We study the signature of primordial non-Gaussianity imprinted on the power spectrum of the 21-cm line differential brightness temperature during dark ages. Employing the perturbative treatment of gravitational clustering, we quantitatively…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-24 Daisuke Yamauchi

The fluctuations produced during cosmic inflation may exhibit non-Gaussian characteristics that are imprinted in the large-scale structure of the Universe. This non-Gaussian imprint is an ultra-large scale signal that can be detected using…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-11 Mponeng Kopana , Sheean Jolicoeur , Roy Maartens

Surveys of the matter distribution contain `fossil' information on possible non-Gaussianity that is generated in the primordial Universe. This primordial signal survives only on the largest scales where cosmic variance is strongest. By…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-10 Sheean Jolicoeur , Roy Maartens , Simthembile Dlamini

Constraints on primordial non-Gaussianity (PNG) will shed light on the origin of primordial fluctuations and the physics of the early universe. The intensity mapping technique is a promising probe of structure formation on large scales; at…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Azadeh Moradinezhad Dizgah , Garrett K. Keating

We present measurements of the bispectrum of dark matter halos in numerical simulations with non-Gaussian initial conditions of the local type. We show, in the first place, that the overall effect of primordial non-Gaussianity on the halo…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Emiliano Sefusatti , Martin Crocce , Vincent Desjacques

We investigate the possibility of performing cosmological studies in the redshift range $2.5<z<5$ through suitable extensions of existing and upcoming radio-telescopes like CHIME, HIRAX and FAST. We use the Fisher matrix technique to…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-11 Andrej Obuljen , Emanuele Castorina , Francisco Villaescusa-Navarro , Matteo Viel

Primordial non-Gaussianity is a crucial test of inflationary cosmology. We consider the impact of non-Gaussianity on the ionization power spectrum from 21 cm emission during the epoch of reionization. We focus on the power spectrum on large…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-30 Shahab Joudaki , Olivier Dore , Luis Ferramacho , Manoj Kaplinghat , Mario G. Santos

Upcoming galaxy redshift surveys promise to significantly improve current limits on primordial non-Gaussianity (PNG) through measurements of 2- and 3-point correlation functions in Fourier space. However, realizing the full potential of…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-19 Azadeh Moradinezhad Dizgah , Matteo Biagetti , Emiliano Sefusatti , Vincent Desjacques , Jorge Noreña

Recent precision cosmological parameter constraints imply that the spatial curvature of the Universe is essentially dynamically negligible - but only if relatively strong assumptions are made about the equation of state of dark energy (DE).…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-02 Amadeus Witzemann , Philip Bull , Chris Clarkson , Mario G. Santos , Marta Spinelli , Amanda Weltman

The bispectrum is a 3-point statistic with the potential to provide additional information beyond power spectra analyses of survey datasets. Radio telescopes which broadly survey the 21cm emission from neutral hydrogen (HI) are a promising…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-11 Steven Cunnington , Catherine Watkinson , Alkistis Pourtsidou

Neutral hydrogen (HI) $21$-cm intensity mapping (IM) is a promising probe of the large-scale structures in the Universe. However, a few orders of magnitude brighter foregrounds obscure the IM signal. Here we use the Tapered Gridded…

We forecast constraints on primordial non-Gaussianity (PNG) and bias parameters from measurements of galaxy power spectrum and bispectrum in future radio continuum and optical surveys. In the galaxy bispectrum, we consider a comprehensive…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-04 Dionysios Karagiannis , Andrei Lazanu , Michele Liguori , Alvise Raccanelli , Nicola Bartolo , Licia Verde

Modified gravity theories offer a well-motivated extension of General Relativity and provide a possible explanation for the late-time accelerated expansion of the Universe. Among them, $f(R)$ gravity represents a minimal and theoretically…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-06 Yanling Song , Yu Sang , Linfeng Xiao , Boyu Zhang , Bin Wang

Measuring one-point statistics in redshifted 21 cm intensity maps offers an opportunity to explore non-Gaussian features of the early universe. We assess the impact of instrumental effects on measurements made with the Hydrogen Epoch of…

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