N-body simulations with generic non-Gaussian initial conditions I: Power
  Spectrum and halo mass function
  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). We plan to
make the simulations outputs available to the community via the non-Gaussian
simulations comparison project web site
http://icc.ub.edu/~liciaverde/NGSCP.html.
