Francis-Yan Cyr-Racine, Fabian Schmidt
Many models of inflation predict oscillatory features in the bispectrum of
primordial fluctuations. Since it has been shown that primordial
non-Gaussianity can lead to a scale-dependent halo bias, we investigate the
effect of oscillations in the three-point function on the clustering of
dark-matter halos. Interestingly, we find that features in the inflaton
potential such as oscillations or sharp steps get imprinted in the mass
dependence of the non-Gaussian halo bias. In this paper, we focus on models
displaying a sharp feature in the inflaton potential as well as Resonant
non-Gaussianity. In both cases, we find a strong scale dependence for the
non-Gaussian halo bias with a slope similar to that of the local model. In the
resonant case, we find that the non-Gaussian bias oscillates with halo mass, a
novel feature that is unique to this type of models. In the case of a sharp
feature in the inflaton potential, we find that the clustering of halos is
enhanced at the mass scale corresponding to the Fourier mode that exited the
horizon when the inflaton was crossing the feature in the potential. Both of
these are new effects that open the possibility of characterizing the
inflationary potential with large-scale-structure surveys. We briefly discuss
the prospects for detecting these non-Gaussian effects.
View original:
http://arxiv.org/abs/1106.2806
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