The cosmic neutrino background and the age of the Universe

@article{Bernardis2008TheCN,
  title={The cosmic neutrino background and the age of the Universe},
  author={Francesco de Bernardis and Alessandro Melchiorri and Licia Verde and Raul Jimenez},
  journal={Journal of Cosmology and Astroparticle Physics},
  year={2008},
  volume={2008},
  pages={020}
}
We discuss the cosmological degeneracy of the age of the Universe, the Hubble parameter and the effective number of relativistic particles Neff. We show that independent determinations of the Hubble parameter H(z) such as those recently provided by Simon et al (2005 Phys. Rev. D 71 123001), combined with other cosmological data sets, can provide the most stringent constraints on Neff, yielding Neff = 3.7−1.2+1.1 at 95% confidence level. A neutrino background is detected with high significance… 

Figures and Tables from this paper

New constraints on cosmological parameters and neutrino properties using the expansion rate of the Universe to z~1.75
We have assembled a compilation of observational Hubble parameter measurements estimated with the differential evolution of cosmic chronometers, in the redshift range 0 4 at 95% CL (74% CL) using the
Improved cosmological parameter constraints from CMB and H(z) data
We discuss the cosmological degeneracies among the Hubble parameter H(z), the age of the Universe and cosmological parameters describing simple variations from the minimal ΛCDM (CDM: cold dark
Constraining the time evolution of dark energy, curvature and neutrino properties with cosmic chronometers
We use the latest compilation of observational H(z) measurements obtained with cosmic chronometers in the redshift range $0<z<2$ to place constraints on cosmological parameters. We consider the
Constraints on the reheating temperature of the universe from WMAP-5 and future perspectives
We report new constraints on the reheating temperature of the Universe by analyzing the Cosmic Microwave Background data from the WMAP five year survey. From WMAP-5 data alone we found an upper limit
Constraints on neutrino physics from cosmology
We discuss the latest constraints from cosmology on the neutrino number and mass. We show that the cosmological data we considered are clearly suggesting the presence for an extra relativistic
Neutrino constraints from future nearly all-sky spectroscopic galaxy surveys
We examine whether future, nearly all-sky galaxy redshift surveys, in combination with CMB priors, will be able to detect the signature of the cosmic neutrino background and determine the absolute
The importance of local measurements for cosmology
We explore how local, cosmology-independent measurements of the Hubble constant and the age of the Universe help to provide a powerful consistency check of the currently favored cosmological model
Decaying neutrinos: The long way to isotropy
We investigate a scenario in which neutrinos are coupled to a pseudoscalar degree of freedom ϕ and where decays ν 1 → ν 2 + ϕ and inverse decays are the responsible mechanism for obtaining
Probing the effective number of neutrino species with the cosmic microwave background
We discuss how much we can probe the effective number of neutrino species N{sub {nu}} with the cosmic microwave background alone. Using the data of the WMAP, ACBAR, CBI, and BOOMERANG experiments, we
Anisotropies in the cosmic neutrino background after Wilkinson Microwave Anisotropy Probe five-year data
We search for the presence of cosmological neutrino background (CNB) anisotropies in recent Wilkinson Microwave Anisotropy Probe (WMAP) five-year data using their signature imprinted on modifications
...
1
2
3
...

References

SHOWING 1-10 OF 81 REFERENCES
Precision Detection of the Cosmic Neutrino Background
In the standard big bang cosmology the canonical value for the ratio of relic neutrinos to cosmic microwave background (CMB) photons is 9/11. Within the framework of the standard model of particle
A precision calculation of the effective number of cosmological neutrinos
Abstract The neutrino energy density of the Universe can be conveniently parametrized in terms of the so-called effective number of neutrinos, Nνeff. This parameter enters in several cosmological
Cosmological Neutrino Background Revisited
We solve the Boltzmann equation for cosmological neutrinos around the epoch of the electron-positron annihilation in order to verify the freeze-out approximation and to compute accurately the
The impact of an extra background of relativistic particles on the cosmological parameters derived from the cosmic microwave background
Recent estimates of cosmological parameters derived from cosmic microwave background (CMB) anisotropies are based on the assumption that we know the precise amount of energy density in relativistic
Neutrino masses and the number of neutrino species from WMAP and 2dFGRS
We have performed a thorough analysis of the constraints which can be put on neutrino parameters from cosmological observations, most notably those from the WMAP satellite and the 2dF galaxy survey.
Constraints on the cosmic neutrino background
The radiative component of the Universe has a characteristic impact on both large-scale structure (LSS) and the cosmic microwave background radiation (CMB). We use the recent WMAP data, together with
Precision cosmology and the density of baryons in the universe.
TLDR
It is clarified precisely what the two methods determine and pointed out that differing values for the baryon density can indicate either an inconsistency or physics beyond the standard models of cosmology and particle physics.
Structure formation with strongly interacting neutrinos - implications for the cosmological neutrino mass bound
We investigate a model where neutrinos are strongly coupled to a new, light scalar field. In this model neutrinos annihilate as soon as they become non-relativistic in the early universe, and a
Present bounds on the relativistic energy density in the Universe from cosmological observables
We discuss the present bounds on the relativistic energy density in the Universe parametrized in terms of the effective number of neutrinos Nνeff using the most recent cosmological data on cosmic
Constraints on the Equation of State of Dark Energy and the Hubble Constant from Stellar Ages and the Cosmic Microwave Background
We place constraints on the redshift-averaged, effective value of the equation of state of dark energy, w, using only the absolute ages of Galactic stars and the observed position of the first peak
...
1
2
3
4
5
...