The Effect of Local non-Gaussianity on the Matter Bispectrum at Small Scales

Abstract

We compute the matter bispectrum in the presence of primordial local non-Gaussianity over a wide range of scales, including the very small nonlinear ones. We use the Halo Model approach, considering non-Gaussian corrections to the halo profiles, the halo mass function and the bias functions. We compare our results in the linear and mildly nonlinear scales to a large ensemble of Gaussian and non-Gaussian numerical simulations. We consider both squeezed and equilateral configurations, at redshift z = 0 and z = 1. For z = 0, the deviations between the Halo Model and the simulations are smaller than 10% in the squeezed limit, both in the Gaussian and non-Gaussian cases. The Halo Model allows to make predictions on scales much smaller than those reached by numerical simulations. For local non-Gaussian initial conditions with a parameter fNL = 100, we find an enhancement of the bispectrum in the squeezed configuration k = k3 = k2 >> k1 \sim 0.01 h^{-1} Mpc, of \sim 15% and \sim 25% on scales k \sim 1 h^{-1} Mpc, at z = 0 and z = 1 respectively. This is mainly due to the non-Gaussian corrections in the linear bias. Finally we provide a very simple expression valid for any scenario, i.e. for any choice of the halo profile, mass and bias functions, which allow for a fast evaluation of the bispectrum on squeezed configurations.

34 pages, 10 figures, Submitted to JCAP

References in corpus (20)

• The imprints of primordial non-gaussianities on large-scale structure: scale dependent bias and abundance of virialized objects
• Primordial Non-Gaussianities from Inflation Models
• Nonlinear Evolution of Baryon Acoustic Oscillations
• Effects of Scale-Dependent Non-Gaussianity on Cosmological Structures
• Non-Gaussianities in two-field inflation
• The bispectrum of galaxies from high-redshift galaxy surveys: primordial non-Gaussianity and non-linear galaxy bias
• Primordial non-gaussianity, statistics of collapsed objects, and the Integrated Sachs-Wolfe effect
• Non-Gaussianity from Preheating
• Non-Gaussian Spikes from Chaotic Billiards in Inflation Preheating
• Signature of Primordial Non-Gaussianity on Matter Power Spectrum
• Effects and Detectability of Quasi-Single Field Inflation in the Large-Scale Structure and Cosmic Microwave Background
• The Three-Point Correlation Function of Luminous Red Galaxies in the Sloan Digital Sky Survey
• Evolution of Massive Haloes in non-Gaussian Scenarios
• An analytic model for the bispectrum of galaxies in redshift space
• Primordial non-Gaussianity in the large scale structure of the Universe
• Non-Gaussianity from massless preheating
• Nonlinear clustering in models with primordial non-Gaussianity: the halo model approach
• Excursion Set Halo Mass Function and Bias in a Stochastic Barrier Model of Ellipsoidal Collapse
• Excursion Set Theory for generic moving barriers and non-Gaussian initial conditions
• Multi-Point Propagators for Non-Gaussian Initial Conditions

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