6533b7d2fe1ef96bd125f57f
RESEARCH PRODUCT
N-body simulations with generic non-Gaussian initial conditions I: Power Spectrum and halo mass function
Licia VerdeLicia VerdeLotfi BoubekeurLotfi BoubekeurChristian Wagnersubject
AstrofísicaCosmology and Nongalactic Astrophysics (astro-ph.CO)Field (physics)GaussianFOS: Physical sciencesAstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsAstrophysics01 natural sciencesSeparable spacesymbols.namesakeComponent (UML)0103 physical sciencesStatistical physics010303 astronomy & astrophysicsPhysicsCosmologia010308 nuclear & particles physicsHalo mass functionSpectral densityAstronomy and AstrophysicsCosmologysymbolsSignature (topology)BispectrumAstrophysics - Cosmology and Nongalactic Astrophysicsdescription
We address the issue of setting up generic non-Gaussian initial conditions for N-body simulations. We consider inflationary-motivated primordial non-Gaussianity where the perturbations in the Bardeen potential are given by a dominant Gaussian part plus a non-Gaussian part specified by its bispectrum. The approach we explore here is suitable for any bispectrum, i.e. it does not have to be of the so-called separable or factorizable form. The procedure of generating a non-Gaussian field with a given bispectrum (and a given power spectrum for the Gaussian component) is not univocal, and care must be taken so that higher-order corrections do not leave a too large signature on the power spectrum. This is so far a limiting factor of our approach. We then run N-body simulations for the most popular inflationary-motivated non-Gaussian shapes. The halo mass function and the non-linear power spectrum agree with theoretical analytical approximations proposed in the literature, even if they were so far developed and tested only for a particular shape (the local one).
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2010-06-30 |