The bispectrum of galaxies from highredshift galaxy surveys: Primordial nonGaussianity and nonlinear galaxy bias
Abstract
The greatest challenge in the interpretation of galaxy clustering data from any surveys is galaxy bias. Using a simple Fisher matrix analysis, we show that the bispectrum provides an excellent determination of linear and nonlinear bias parameters of intermediate and highz galaxies, when all measurable triangle configurations down to mildly nonlinear scales, where perturbation theory is still valid, are included. The bispectrum is also a powerful probe of primordial nonGaussianity. The planned galaxy surveys at z {approx}> 2 should yield constraints on nonGaussian parameters, f{sub NL}{sup loc.} and f{sub NL}{sup eq.}, that are comparable to, or even better than, those from CMB experiments. We study how these constraints improve with volume, redshift range, as well as the number density of galaxies. Finally we show that a halo occupation distribution may be used to improve these constraints further by lifting degeneracies between gravity, bias, and primordial nonGaussianity.
 Authors:
 Publication Date:
 Research Org.:
 Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 918733
 Report Number(s):
 FERMILABPUB07107A
arXiv eprint number arXiv:0705.0343; TRN: US200819%%437
 DOE Contract Number:
 AC0207CH11359
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Phys.Rev.D76:083004,2007
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DISTRIBUTION; GALAXIES; OCCUPATIONS; PERTURBATION THEORY; PROBES; RED SHIFT; Astrophysics
Citation Formats
Sefusatti, Emiliano, /Fermilab, Komatsu, Eiichiro, and /Texas U., Astron. Dept.. The bispectrum of galaxies from highredshift galaxy surveys: Primordial nonGaussianity and nonlinear galaxy bias. United States: N. p., 2007.
Web. doi:10.1103/PhysRevD.76.083004.
Sefusatti, Emiliano, /Fermilab, Komatsu, Eiichiro, & /Texas U., Astron. Dept.. The bispectrum of galaxies from highredshift galaxy surveys: Primordial nonGaussianity and nonlinear galaxy bias. United States. doi:10.1103/PhysRevD.76.083004.
Sefusatti, Emiliano, /Fermilab, Komatsu, Eiichiro, and /Texas U., Astron. Dept.. Tue .
"The bispectrum of galaxies from highredshift galaxy surveys: Primordial nonGaussianity and nonlinear galaxy bias". United States.
doi:10.1103/PhysRevD.76.083004. https://www.osti.gov/servlets/purl/918733.
@article{osti_918733,
title = {The bispectrum of galaxies from highredshift galaxy surveys: Primordial nonGaussianity and nonlinear galaxy bias},
author = {Sefusatti, Emiliano and /Fermilab and Komatsu, Eiichiro and /Texas U., Astron. Dept.},
abstractNote = {The greatest challenge in the interpretation of galaxy clustering data from any surveys is galaxy bias. Using a simple Fisher matrix analysis, we show that the bispectrum provides an excellent determination of linear and nonlinear bias parameters of intermediate and highz galaxies, when all measurable triangle configurations down to mildly nonlinear scales, where perturbation theory is still valid, are included. The bispectrum is also a powerful probe of primordial nonGaussianity. The planned galaxy surveys at z {approx}> 2 should yield constraints on nonGaussian parameters, f{sub NL}{sup loc.} and f{sub NL}{sup eq.}, that are comparable to, or even better than, those from CMB experiments. We study how these constraints improve with volume, redshift range, as well as the number density of galaxies. Finally we show that a halo occupation distribution may be used to improve these constraints further by lifting degeneracies between gravity, bias, and primordial nonGaussianity.},
doi = {10.1103/PhysRevD.76.083004},
journal = {Phys.Rev.D76:083004,2007},
number = ,
volume = ,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}

The greatest challenge in the interpretation of galaxy clustering data from any surveys is galaxy bias. Using a simple Fisher matrix analysis, we show that the bispectrum provides an excellent determination of linear and nonlinear bias parameters of intermediate and highz galaxies, when all measurable triangle configurations down to mildly nonlinear scales, where perturbation theory is still valid, are included. The bispectrum is also a powerful probe of primordial nonGaussianity. The planned galaxy surveys at z > or approx. 2 should yield constraints on nonGaussian parameters, f{sub NL}{sup loc.} and f{sub NL}{sup eq.}, that are comparable to, or even bettermore »

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