Istituto Nazionale di Fisica Nucleare, Padova, Italy
I will present a comparison between theoretical models and numerical simulations for the matter bispectrum of large-scale structure at low redshifts. This comparison will highlight the advantages and shortcomings of the various perturbative and halo models; in particular I will show that there is a significant underprediction of the bispectrum of the standard halo model on intermediate scales for z>0.
Based on the shapes of these theoretical models and the N-body simualations, I will show how a simple phenomenological model based on the halo model, fitting the simulations very well, can be developed, as a sum of three simple shapes with scale-dependent amplitudes: the tree-level gravitational bispectrum, the squeezed shape and the constant shape.
I will also show how this model can be extended to primordial non-Gaussianity of the local and equilateral types.
2016 October 19, 13:30
Centro de Astrofísica da Universidade do Porto (Auditorium)
Rua das Estrelas, 4150-762 Porto