2013/04/22 by Eleonora Di Valentino, Alessandro Melchiorri, A. Melchiorri +1 · 2 citations
Physics and Astronomy · #Age of the universe #Astronomy #Astrophysics #Axion #Cosmic background radiation #Cosmic microwave background #Cosmology #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark energy #Dark matter #Dark radiation #Decoupling (probability) #Hubble's law #Neutrino #Neutrino oscillation #Particle physics #Particle physics theoretical and experimental studies #Physics #Planck #Quantum mechanics #South Pole Telescope #Sterile neutrino #astro-ph.CO
paper · pdf · doi:10.1088/1475-7516/2013/11/018
arxiv created 2013/04/22 · openalex publication_date 2013/11/07 · arxiv updated 2015/06/15 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Recent Cosmic Microwave Background (CMB) results from the Planck satellite, combined with previous CMB data and Hubble constant measurements from the Hubble Space Telescope, provide a constraint on the effective number of relativistic degrees of freedom 3.62 +0.50 −0.48 at 95% CL. New Planck data provide a unique opportunity to place limits on models containing relativistic species at the decoupling epoch. We present here the bounds on sterile neutrino models combining Planck data with galaxy clustering information. Assuming N eff active plus sterile massive neutrino species, in the case of a Planck+WP+HighL+HST analysis we find m ν, sterile eff < 0.36 eV and 3.14 < N eff < 4.15 at 95% CL, while using Planck+WP+HighL data in combination with the full shape of the galaxy power spectrum from the Baryon Oscillation Spectroscopic Survey BOSS Data Relase 9 measurements, we find that 3.30 < N eff < 4.43 and m ν, sterile eff < 0.33 eV both at 95% CL with the three active neutrinos having the minimum mass allowed in the normal hierarchy scheme, i.e. ∑ m ν ∼ 0.06 eV. These values compromise the viability of the (3+2) massive sterile neutrino models for the parameter region indicated by global fits of neutrino oscillation data. Within the (3+1) massive sterile neutrino scenario, we find m ν, sterile eff < 0.34 eV at 95% CL. While the existence of one extra sterile massive neutrino state is compatible with current oscillation data, the values for the sterile neutrino mass preferred by oscillation analyses are significantly higher than the current cosmological bound. We review as well the bounds on extended dark sectors with additional light species based on the latest Planck CMB observations.