Anisotropies in the Cosmic Neutrino Background after WMAP 5-year Data

Abstract

We search for the presence of cosmological neutrino background (CNB) anisotropies in recent WMAP 5-year data using their signature imprinted on modifications to cosmic microwave background (CMB) anisotropy power spectrum. By parametrizing the neutrino background anisotropies with the speed viscosity parameter $c_\vis$, we find that the WMAP 5-year data alone provide only a weak indication for CNB anisotropies with $c_\vis^2 > 0.06$ at the 95% confidence level. When we combine CMB anisotropy data with measurements of galaxy clustering, SN-Ia Hubble diagram, and other cosmological information, the detection increases to $c_\vis^2 > 0.16$ at the same 95% confidence level. Future data from Planck, combined with a weak lensing survey such as the one expected with DUNE from space, will be able to measure the CNB anisotropy parameter at about 10% accuracy. We discuss the degeneracy between neutrino background ansiotropies and other cosmological para meters such as the number of effective neutrinos species and the dark energy equation of state.

7 Pages, 7 Figures

References in corpus (35)

• Cosmological parameters from CMB and other data: a Monte-Carlo approach
• Final Results from the Hubble Space Telescope Key Project to Measure the Hubble Constant
• The Supernova Legacy Survey: Measurement of Omega_M, Omega_Lambda and w from the First Year Data Set
• The 2dF Galaxy Redshift Survey: Power-spectrum analysis of the final dataset and cosmological implications
• Stable clustering, the halo model and nonlinear cosmological power spectra
• Halo Models of Large Scale Structure
• Cosmological Perturbation Theory in the Synchronous and Conformal Newtonian Gauges
• Cosmological Perturbation Theory in the Synchronous vs. Conformal Newtonian Gauge
• The 3D power spectrum of galaxies from the SDSS
• Cosmological Constraints from the SDSS Luminous Red Galaxies
• Weak Gravitational Lensing of the CMB
• Karhunen-Loeve eigenvalue problems in cosmology: how should we tackle large data sets?
• Big-Bang Nucleosynthesis Predictions for Precision Cosmology
• Cosmological-Parameter Determination with Microwave Background Maps
• Structure Formation with Generalized Dark Matter
• Extended Mosaic Observations with the Cosmic Background Imager
• Effect of Photometric Redshift Uncertainties on Weak Lensing Tomography
• The Effect of Physical Assumptions on the Calculation of Microwave Background Anisotropies
• Reconstructing Projected Matter Density from Cosmic Microwave Background
• Power Spectrum Covariance of Weak Gravitational Lensing
• Probing reheating temperature of the universe with gravitational wave background
• Neutrinoless Universe
• Neutrino Mass and Dark Energy from Weak Lensing
• Structure formation with strongly interacting neutrinos - implications for the cosmological neutrino mass bound
• Cosmological Signatures of Interacting Neutrinos
• Measuring Dark Matter Power Spectrum from Cosmic Microwave Background
• Observational bounds on the cosmic radiation density
• Measuring neutrino masses and dark energy with weak lensing tomography
• Observationally Determining the Properties of Dark Matter
• Direct Signature of Evolving Gravitational Potential from Cosmic Microwave Background
• Indication for Primordial Anisotropies in the Neutrino Background from WMAP and SDSS
• Present bounds on the relativistic energy density in the Universe from cosmological observables
• The Cosmic Neutrino Background and the Age of the Universe
• Weighing Neutrinos: Weak Lensing Approach
• Cosmological Parameter Estimation from the CMB

Cited by in corpus (22)

• Cosmology and Fundamental Physics with the Euclid Satellite
• Cosmology and fundamental physics with the Euclid satellite
• The Neutrino Puzzle: Anomalies, Interactions, and Cosmological Tensions
• How Massless Neutrinos Affect the Cosmic Microwave Background Damping Tail
• Limits on Neutrino-Neutrino Scattering in the Early Universe
• The Case for Dark Radiation
• Dark goo: Bulk viscosity as an alternative to dark energy
• Neutrino physics from precision cosmology
• Flavor-specific Interaction Favors Strong Neutrino Self-coupling in the Early Universe
• Are cosmological neutrinos free-streaming?
• Constraints on neutrino and dark radiation interactions using cosmological observations
• Constraining Modified Gravity with Euclid
• The two-mode puzzle: Confronting self-interacting neutrinos with the full shape of the galaxy power spectrum
• Dark Radiation in extended cosmological scenarios
• Origin of Delta N_eff as a Result of an Interaction between Dark Radiation and Dark Matter
• Delayed Recombination and Cosmic Parameters
• The Cosmic Neutrino Background Anisotropy - Linear Theory
• Low-Redshift Constraints on Covariant Canonical Gauge Theory of Gravity
• Improved Cosmological Parameter Constraints from CMB and H(z) Data
• Decaying neutrinos: The long way to isotropy
• Cosmic Neutrino Background as a Ferromagnet
• Sound Speed and Viscosity of Semi-Relativistic Relic Neutrinos