English
Related papers

Related papers: Detecting the relativistic bispectrum in 21cm inte…

200 papers

General relativity is exquisitely tested in strong-field regimes, yet its validity on cosmological scales remains largely unexplored. Upcoming wide and deep large-scale structure surveys will access the ultra-large, linear scales where…

Given the important role that the galaxy bispectrum has recently acquired in cosmology and the scale and precision of forthcoming galaxy clustering observations, it is timely to derive the full expression of the large-scale bispectrum going…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-31 Daniele Bertacca , Alvise Raccanelli , Nicola Bartolo , Michele Liguori , Sabino Matarrese , Licia Verde

Upcoming large-scale structure surveys will be able to measure new features in the galaxy two point correlation function. Relativistic effects appear on large scales as subtle corrections to redshift-space distortions, showing up as a…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-29 Daniel Sobral-Blanco , Camille Bonvin , Chris Clarkson , Roy Maartens

The high-redshift 21-cm signal of neutral hydrogen is expected to be observed within the next decade and will reveal epochs of cosmic evolution that have been previously inaccessible. Due to the lack of observations, many of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-16 Aviad Cohen , Anastasia Fialkov , Rennan Barkana

Intensity maps of the 21cm emission line of neutral hydrogen are lensed by intervening large-scale structure, similar to the lensing of the cosmic microwave background temperature map. We extend previous work by calculating the lensing…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-16 Rahul Kothari , Roy Maartens

Observing the Epoch of Reionisation using 21cm radio interferometry has proven to be a challenging task. Extraction of the extremely faint redshifted signal is complicated by the presence of bright foregrounds, radio frequency interference…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-30 Sohini Dutta , Philip Bull , Jacob Burba , Michael J. Wilensky , Zheng Zhang , Ainulnabilah Nasirudin

In a previous paper we presented the results of applying machine learning to classify whether an HI 21-cm absorption spectrum arises in a source intervening the sight-line to a more distant radio source or within the host of the radio…

Instrumentation and Methods for Astrophysics · Physics 2021-07-14 S. J. Curran

The next generation of telescopes will usher in an era of precision cosmology, capable of determining the cosmological model to beyond the percent level. For this to be effective, the theoretical model must be understood to at least the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Obinna Umeh , Chris Clarkson , Roy Maartens

[Abridged] The spatially averaged global spectrum of the redshifted 21cm line has generated much experimental interest, for it is potentially a direct probe of the Epoch of Reionization and the Dark Ages. Since the cosmological signal here…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-07 Adrian Liu , Jonathan R. Pritchard , Max Tegmark , Abraham Loeb

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

Planned efforts to probe the largest observable distance scales in future cosmological surveys are motivated by a desire to detect relic correlations left over from inflation, and the possibility of constraining novel gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-11 Caroline Guandalin , Julian Adamek , Philip Bull , Chris Clarkson , L. Raul Abramo , Louis Coates

We describe the effects of weak gravitational lensing by cosmological large scale structure on the diffuse emission of 21 centimeter radiation from neutral hydrogen at high redshifts during the era of reionization. The ability to observe…

Astrophysics · Physics 2010-11-11 Kaisey S. Mandel , Matias Zaldarriaga

The bispectrum will play an important role in future galaxy surveys. On large scales it is a key probe for measuring primordial non-Gaussianity which can help differentiate between different inflationary models and other theories of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-12 Chris Clarkson , Eline M. de Weerd , Sheean Jolicoeur , Roy Maartens , Obinna Umeh

Radial redshift-space distortions due to peculiar velocities and other light-cone effects shape the maps we build of the Universe. We address the open question of their impact onto the monopole moment of the galaxy power spectrum, $P_0(k)$.…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-01 Mohamed Yousry Elkhashab , Cristiano Porciani , Daniele Bertacca

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

The redshifted 21-cm monopole is expected to be a powerful probe of the epoch of the first stars and galaxies ($10<z<35$). The global 21-cm signal is sensitive to the thermal and ionization state of hydrogen gas and thus provides a tracer…

We investigate the prospect of constraining scalar field dark energy models using HI 21-cm intensity mapping surveys. We consider a wide class of coupled scalar field dark energy models whose predictions about the background cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Azam Hussain , Shruti Thakur , Tapomoy Guha Sarkar , Anjan A Sen

We present the complete expression for the next-to-leading (1-loop) order galaxy power spectrum and the leading-order galaxy bispectrum in redshift space in the general bias expansion, or equivalently the effective field theory of biased…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-11 Vincent Desjacques , Donghui Jeong , Fabian Schmidt

In a galaxy redshift survey the objects to be targeted for spectra are selected from a photometrically observed sample. The observed magnitudes and colours of galaxies in this parent sample will be affected by their peculiar velocities,…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-25 Shadab Alam , Rupert A. C. Croft , Shirley Ho , Hongyu Zhu , Elena Giusarma

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