The gravitational and lensing-ISW bispectrum of 21 cm radiation
File(s)
Published version
OA Location
Author(s)
Schmit, Claude J
Heavens, Alan F
Pritchard, Jonathan R
Type
Journal Article
Abstract
Cosmic microwave background experiments from COBE to Planck have launched cosmology into an era of precision science, where many cosmological parameters are now determined to the per cent level. Next-generation telescopes, focusing on the cosmological 21 cm signal from neutral hydrogen, will probe enormous volumes in the low-redshift Universe, and have the potential to determine dark energy properties and test modifications of Einstein’s gravity. We study the 21 cm bispectrum due to gravitational collapse as well as the contribution by line-of-sight perturbations in the form of the lensing-ISW bispectrum at low redshifts (z ∼ 0.35−3), targeted by upcoming neutral hydrogen intensity mapping experiments. We compute the expected bispectrum amplitudes and use a Fisher forecast model to compare power spectrum and bispectrum observations of intensity mapping surveys by Canadian Hydrogen Intensity Mapping Experiment (CHIME), MeerKAT, and SKA-mid. We find that combined power spectrum and bispectrum observations have the potential to decrease errors on the cosmological parameters by an order of magnitude compared to Planck. Finally, we compute the contribution of the lensing-ISW bispectrum, and find that, unlike for the cosmic microwave background analyses, it can safely be ignored for 21 cm bispectrum observations.
Date Issued
2019-03-01
Date Acceptance
2018-12-06
Citation
Monthly Notices of the Royal Astronomical Society, 2019, 483 (3), pp.4259-4275
ISSN
0035-8711
Publisher
Oxford University Press (OUP)
Start Page
4259
End Page
4275
Journal / Book Title
Monthly Notices of the Royal Astronomical Society
Volume
483
Issue
3
Copyright Statement
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Sponsor
Commission of the European Communities
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000462280000098&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
638743
Subjects
Science & Technology
Physical Sciences
Astronomy & Astrophysics
methods: statistical
cosmological parameters
large-scale structure of Universe
PRIMORDIAL NON-GAUSSIANITY
I MASS FUNCTION
H-I
CENTIMETER FLUCTUATIONS
POWER SPECTRUM
GALAXIES
CONSTRAINTS
COSMOLOGY
CFHTLENS
SHEAR
Publication Status
Published
Date Publish Online
2018-12-17