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Title: Nonlinear modulation of the HI power spectrum on ultra-large scales. I

Abstract

Intensity mapping of the neutral hydrogen brightness temperature promises to provide a three-dimensional view of the universe on very large scales. Nonlinear effects are typically thought to alter only the small-scale power, but we show how they may bias the extraction of cosmological information contained in the power spectrum on ultra-large scales. For linear perturbations to remain valid on large scales, we need to renormalize perturbations at higher order. In the case of intensity mapping, the second-order contribution to clustering from weak lensing dominates the nonlinear contribution at high redshift. Renormalization modifies the mean brightness temperature and therefore the evolution bias. It also introduces a term that mimics white noise. These effects may influence forecasting analysis on ultra-large scales.

Authors:
; ;  [1]
  1. Department of Physics, University of the Western Cape, Robert Sobukwe Road, Bellville 7535 (South Africa)
Publication Date:
OSTI Identifier:
22524908
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BRIGHTNESS; COSMOLOGY; DISTURBANCES; EVOLUTION; GRAVITATIONAL LENSES; HYDROGEN; MAPPING; MODULATION; NOISE; NONLINEAR PROBLEMS; RED SHIFT; RENORMALIZATION; UNIVERSE

Citation Formats

Umeh, Obinna, Maartens, Roy, and Santos, Mario, E-mail: umeobinna@gmail.com, E-mail: roy.maartens@gmail.com, E-mail: mgrsantos@uwc.ac.za. Nonlinear modulation of the HI power spectrum on ultra-large scales. I. United States: N. p., 2016. Web. doi:10.1088/1475-7516/2016/03/061.
Umeh, Obinna, Maartens, Roy, & Santos, Mario, E-mail: umeobinna@gmail.com, E-mail: roy.maartens@gmail.com, E-mail: mgrsantos@uwc.ac.za. Nonlinear modulation of the HI power spectrum on ultra-large scales. I. United States. doi:10.1088/1475-7516/2016/03/061.
Umeh, Obinna, Maartens, Roy, and Santos, Mario, E-mail: umeobinna@gmail.com, E-mail: roy.maartens@gmail.com, E-mail: mgrsantos@uwc.ac.za. Tue . "Nonlinear modulation of the HI power spectrum on ultra-large scales. I". United States. doi:10.1088/1475-7516/2016/03/061.
@article{osti_22524908,
title = {Nonlinear modulation of the HI power spectrum on ultra-large scales. I},
author = {Umeh, Obinna and Maartens, Roy and Santos, Mario, E-mail: umeobinna@gmail.com, E-mail: roy.maartens@gmail.com, E-mail: mgrsantos@uwc.ac.za},
abstractNote = {Intensity mapping of the neutral hydrogen brightness temperature promises to provide a three-dimensional view of the universe on very large scales. Nonlinear effects are typically thought to alter only the small-scale power, but we show how they may bias the extraction of cosmological information contained in the power spectrum on ultra-large scales. For linear perturbations to remain valid on large scales, we need to renormalize perturbations at higher order. In the case of intensity mapping, the second-order contribution to clustering from weak lensing dominates the nonlinear contribution at high redshift. Renormalization modifies the mean brightness temperature and therefore the evolution bias. It also introduces a term that mimics white noise. These effects may influence forecasting analysis on ultra-large scales.},
doi = {10.1088/1475-7516/2016/03/061},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 03,
volume = 2016,
place = {United States},
year = {Tue Mar 01 00:00:00 EST 2016},
month = {Tue Mar 01 00:00:00 EST 2016}
}