Relativistic bias in neutrino cosmologies

Abstract

Halos and galaxies are tracers of the underlying dark matter structures. While their bias is well understood in the case of a simple Universe composed dominantly of dark matter, the relation becomes more complex in the presence of massive neutrinos. Indeed massive neutrinos introduce rich dynamics in the process of structure formation leading to scale-dependent bias. We study this process from the perspective of general relativity employing a simple spherical collapse model. We find a characteristic signature at the neutrino free-streaming scale in addition to a large-scale feature from general relativity. The scale-dependent halo bias opposes the suppression in the matter distribution due to neutrino free-streaming and leads to corrections of a few percent in the halo power spectrum. It is not only sensitive to the sum of the neutrino-masses, but respond to the individual masses. Accurate models for the neutrino bias are a crucial ingredient for the future data analysis and play an important role in constraining the neutrino masses.

20 pages, 10 figures

References in corpus (9)

• Massive neutrinos and cosmology
• Cosmological parameters from combining the Lyman-alpha forest with CMB, galaxy clustering and SN constraints
• The Cosmic Linear Anisotropy Solving System (CLASS) I: Overview
• Nonlinear power spectrum in the presence of massive neutrinos: perturbation theory approach, galaxy bias and parameter forecasts
• Halo bias in mixed dark matter cosmologies
• Physical effects involved in the measurements of neutrino masses with future cosmological data
• Relativistic N-body simulations with massive neutrinos
• The halo model in a massive neutrino cosmology
• General relativistic weak-field limit and Newtonian N-body simulations

Cited by in corpus (4)

• Redshift-Space Distortions in Lagrangian Perturbation Theory
• Cosmological constraints from the tomographic cross-correlation of DESI Luminous Red Galaxies and Planck CMB lensing
• Cosmological constraints from the cross-correlation of DESI Luminous Red Galaxies with CMB lensing from Planck PR4 and ACT DR6
• Large scale structures: from inflation to today: a brief report