English

Verifying the consistency relation for the scale-dependent bias from local primordial non-Gaussianity

Cosmology and Nongalactic Astrophysics 2017-05-16 v2

Abstract

We measure the large-scale bias of dark matter halos in simulations with non-Gaussian initial conditions of the local type, and compare this bias to the response of the mass function to a change in the primordial amplitude of fluctuations. The two are found to be consistent, as expected from physical arguments, for three halo-finder algorithms which use different Spherical Overdensity (SO) and Friends-of-Friends (FoF) methods. On the other hand, we find that the commonly used prediction for universal mass functions, that the scale-dependent bias is proportional to the first-order Gaussian Lagrangian bias, does not yield a good agreement with the measurements. For all halo finders, high-mass halos show a non-Gaussian bias suppressed by 10-15% relative to the universal mass function prediction. For SO halos, this deviation changes sign at low masses, where the non-Gaussian bias becomes larger than the universal prediction.

Keywords

Cite

@article{arxiv.1611.04901,
  title  = {Verifying the consistency relation for the scale-dependent bias from local primordial non-Gaussianity},
  author = {Matteo Biagetti and Titouan Lazeyras and Tobias Baldauf and Vincent Desjacques and Fabian Schmidt},
  journal= {arXiv preprint arXiv:1611.04901},
  year   = {2017}
}

Comments

12 pages, 6 figures. v2. several improvements: new theory section, new fig.2, added references, matches version published in MNRAS