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DOE OSTI · 22373407

Large-scale 3D galaxy correlation function and non-Gaussianity

Raccanelli, Alvise·Doré, Olivier·Bertacca, Daniele·Maartens, Roy
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Abstract

We investigate the properties of the 2-point galaxy correlation function at very large scales, including all geometric and local relativistic effects --- wide-angle effects, redshift space distortions, Doppler terms and Sachs-Wolfe type terms in the gravitational potentials. The general three-dimensional correlation function has a nonzero dipole and octupole, in addition to the even multipoles of the flat-sky limit. We study how corrections due to primordial non-Gaussianity and General Relativity affect the multipolar expansion, and we show that they are of similar magnitude (when f{sub NL} is small), so that a relativistic approach is needed. Furthermore, we look at how large-scale corrections depend on the model for the growth rate in the context of modified gravity, and we discuss how a modified growth can affect the non-Gaussian signal in the multipoles.

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79 ASTRONOMY AND ASTROPHYSICSCORRECTIONSCORRELATION FUNCTIONSDIPOLESGALAXIESGENERAL RELATIVITY THEORYGEOMETRYGRAVITATIONOCTUPOLESRED SHIFTRELATIVISTIC RANGESIGNALSSKYSPACE

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Raccanelli, Alvise, Doré, Olivier, Bertacca, Daniele, Maartens, Roy. 2014-08-01. Large-scale 3D galaxy correlation function and non-Gaussianity. https://doi.org/10.1088/1475-7516%2F2014%2F08%2F022

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