Alvise Raccanelli, Daniele Bertacca, Olivier Dore, Roy Maartens
We investigate the properties of the 2-point galaxy correlation function at very large scales in presence of non-Gaussianity, when including geometric and relativistic effects. We show that the general full 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 non-Gaussianity and General Relativity affect the multipolar expansion, and we show that they are of similar magnitude (when f_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 conclude discussing how a modified growth can affect the non-Gaussian signal in the multipoles.
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http://arxiv.org/abs/1306.6646
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