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

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We present projected constraints on modified gravity models from the observational technique known as 21 cm intensity mapping, where cosmic structure is detected without resolving individual galaxies. The resulting map is sensitive to both…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Kiyoshi Wesley Masui , Fabian Schmidt , Ue-Li Pen , Patrick McDonald

Primordial non-Gaussianity is an invaluable window into the physical processes that gave rise to the cosmological structure. The presence of local shape PNG imprints a distinct scale-dependent correction to the bias of dark matter tracers…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-15 Azadeh Moradinezhad Dizgah , Garrett K. Keating , Anastasia Fialkov

The Cosmological Principle states that the universe is statistically isotropic and homogeneous on large length scales, typically $\gtrsim 70$Mpc. A detection of significant deviation would help us falsify the simplest models of inflation.…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-26 Bhuwan Joshi , Rahul Kothari

We investigate expected constraints on equilateral-type primordial non-Gaussianities from future/ongoing imaging surveys, making use of the fact that they enhance the halo/galaxy bispectrum on large scales. As model parameters to be…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Ichihiko Hashimoto , Shuntaro Mizuno , Shuichiro Yokoyama

The 21cm emission of neutral hydrogen is a potential probe of the matter distribution in the Universe after reionisation. Cosmological surveys of this line intensity will be conducted in the coming years by the SKAO and HIRAX experiments,…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-16 Dionysios Karagiannis , Roy Maartens , Liantsoa Randrianjanahary

Line intensity mapping using atomic hydrogen (HI) has the potential to efficiently map large volumes of the universe if the signal can be successfully separated from overwhelmingly bright radio foreground emission. This motivates…

The success of HI intensity mapping is largely dependent on how well 21cm foreground contamination can be controlled. In order to progress our understanding further, we present a range of simulated foreground data from four different…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-25 Steven Cunnington , Melis O. Irfan , Isabella P. Carucci , Alkistis Pourtsidou , Jérôme Bobin

The Hydrogen Intensity and Real-time Analysis eXperiment (HIRAX) is an upcoming radio interferometric telescope designed to constrain dark energy through the 21cm intensity mapping of Baryon Acoustic Oscillations (BAO). Instrumental…

Intensity mapping (IM) of spectral lines has the potential to revolutionize cosmology by increasing the total number of observed modes by several orders of magnitude compared to the cosmic microwave background (CMB) anisotropies. In this…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-22 Jurek B. Bauer , David J. E. Marsh , Renée Hložek , Hamsa Padmanabhan , Alex Laguë

The post-reionization $(z \le 6)$ neutral hydrogen (HI) 21-cm intensity mapping signal holds the potential to probe the large scale structures, study the expansion history and constrain various cosmological parameters. Here we apply the…

We investigate the prospects of measuring the cosmic magnification effect by cross-correlating neutral hydrogen intensity mapping (HI IM) maps with background optical galaxies. We forecast the signal-to-noise ratio for HI IM data from…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-10 Amadeus Witzemann , Alkistis Pourtsidou , Mario G. Santos

The future of precision cosmology could benefit from cross-correlations between intensity maps of unresolved neutral hydrogen (HI) and more conventional optical galaxy surveys. A major challenge that needs to be overcome is removing the…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-17 Steven Cunnington , Laura Wolz , Alkistis Pourtsidou , David Bacon

21 cm intensity mapping has arisen as a powerful probe of the high-redshift universe, but its potential is limited by extremely bright foregrounds and high source confusion. In this Letter, we propose a new analysis which can help solve…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-11 Patrick C. Breysse , Christopher J. Anderson , Philippe Berger

Hydrogen 21-cm Line Intensity Mapping offers the unique opportunity to access the Dark Ages and trace the formation and evolution of the large scale structure of the Universe prior to star and galaxy formation. In this work we investigate…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-22 Elena Vanetti , Eleonora Vanzan , Nicola Bellomo , Alvise Raccanelli

The 21-cm intensity mapping (IM) of neutral hydrogen (HI) is a promising tool to probe the large-scale structures. Sky maps of 21-cm intensities can be highly contaminated by different foregrounds, such as Galactic synchrotron radiation,…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-01 Elimboto Yohana , Yin-Zhe Ma , Di Li , Xuelei Chen , Wei-Ming Dai

We investigate future constraints on primordial local-type non-Gaussianity from 21 cm angular power spectrum from minihalos. We particularly focus on the trispectrum of primordial curvature perturbations which are characterized by the…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Toyokazu Sekiguchi , Tomo Takahashi , Hiroyuki Tashiro , Shuichiro Yokoyama

We study primordial non-Gaussian signatures in the redshift-space halo field on non-linear scales, using a quasi-maximum likelihood estimator based on optimally compressed power spectrum and modal bispectrum statistics. We train and…

The normalisation of the matter power spectrum, sigma_8, is an essential ingredient to predict the phenomenology of the low redshift universe. It has been measured using several methods, such as X-ray cluster counts, weak lensing and the…

Astrophysics · Physics 2008-11-26 A. Amara , A. Refregier

Predictions for the ability of 21-cm interferometric experiments to discriminate Epoch of Reionization (EoR) signal models are typically limited by the simplicity of data models, whereby foreground signals and characteristics of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-29 Ainulnabilah Nasirudin , Steven Murray , Cathryn Trott , Bradley Greig , Ronniy Joseph , Chris Power

In the pursuit of primordial non-Gaussianities, we hope to access smaller scales across larger comoving volumes. At low redshift, the search for primordial non-Gaussianities is hindered by gravitational collapse, to which we often associate…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-08 Thomas Flöss , Matteo Biagetti , P. Daniel Meerburg