A generalized local ansatz and its effect on halo bias
- Perimeter Institute for Theoretical Physics, Waterloo, Ontario (Canada)
- Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, Ontario (Canada)
- Department of Physics, University of Michigan, Ann Arbor, Michigan (United States)
Motivated by the properties of early universe scenarios that produce observationally large local non-Gaussianity, we perform N-body simulations with non-Gaussian initial conditions from a generalized local ansatz. The bispectra are schematically of the local shape, but with scale-dependent amplitude. We find that in such cases the size of the non-Gaussian correction to the bias of small and large mass objects depends on the amplitude of non-Gaussianity roughly on the scale of the object. In addition, some forms of the generalized bispectrum alter the scale dependence of the non-Gaussian term in the bias by a fractional power of k. These features may allow significant observational constraints on the particle physics origin of any observed local non-Gaussianity, distinguishing between scenarios where a single field or multiple fields contribute to the curvature fluctuations. While analytic predictions for the non-Gaussian bias agree qualitatively with the simulations, we find numerically a stronger observational signal than expected. This suggests that a more precise understanding of halo formation is needed to fully explain the consequences of primordial non-Gaussianity.
- OSTI ID:
- 22275319
- Journal Information:
- Journal of Cosmology and Astroparticle Physics, Vol. 2011, Issue 03; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
- Country of Publication:
- United States
- Language:
- English
Similar Records
Halo clustering with nonlocal non-Gaussianity
N-body simulations with generic non-Gaussian initial conditions II: halo bias