Light sterile neutrinos and inflationary freedom
Abstract
We perform a cosmological analysis in which we allow the primordial power spectrum of scalar perturbations to assume a shape that is different from the usual powerlaw predicted by the simplest models of cosmological inflation. We parameterize the free primordial power spectrum with a ''piecewise cubic Hermite interpolating polynomial'' (PCHIP). We consider a 3+1 neutrino mixing model with a sterile neutrino having a mass at the eV scale, which can explain the anomalies observed in shortbaseline neutrino oscillation experiments. We find that the freedom of the primordial power spectrum allows to reconcile the cosmological data with a fully thermalized sterile neutrino in the early Universe. Moreover, the cosmological analysis gives us some information on the shape of the primordial power spectrum, which presents a feature around the wavenumber k=0.002 Mpc{sup −1}.
 Authors:
 Department of Physics, University of Torino, Via P. Giuria 1, I–10125 Torino (Italy)
 INFN, Sezione di Torino, Via P. Giuria 1, I–10125 Torino (Italy)
 Dipartimento di Fisica e Astronomia ''G. Galilei'', Università di Padova, and INFN, Sezione di Padova, Via F. Marzolo 8, I–35131 Padova (Italy)
 Publication Date:
 OSTI Identifier:
 22525894
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMOLOGICAL INFLATION; COSMOLOGY; DISTURBANCES; ENERGY SPECTRA; MASS; NEUTRINO OSCILLATION; NEUTRINOS; POLYNOMIALS; SCALARS; UNIVERSE; VISIBLE RADIATION
Citation Formats
Gariazzo, S., Giunti, C., and Laveder, M., Email: gariazzo@to.infn.it, Email: giunti@to.infn.it, Email: laveder@pd.infn.it. Light sterile neutrinos and inflationary freedom. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/04/023.
Gariazzo, S., Giunti, C., & Laveder, M., Email: gariazzo@to.infn.it, Email: giunti@to.infn.it, Email: laveder@pd.infn.it. Light sterile neutrinos and inflationary freedom. United States. doi:10.1088/14757516/2015/04/023.
Gariazzo, S., Giunti, C., and Laveder, M., Email: gariazzo@to.infn.it, Email: giunti@to.infn.it, Email: laveder@pd.infn.it. 2015.
"Light sterile neutrinos and inflationary freedom". United States.
doi:10.1088/14757516/2015/04/023.
@article{osti_22525894,
title = {Light sterile neutrinos and inflationary freedom},
author = {Gariazzo, S. and Giunti, C. and Laveder, M., Email: gariazzo@to.infn.it, Email: giunti@to.infn.it, Email: laveder@pd.infn.it},
abstractNote = {We perform a cosmological analysis in which we allow the primordial power spectrum of scalar perturbations to assume a shape that is different from the usual powerlaw predicted by the simplest models of cosmological inflation. We parameterize the free primordial power spectrum with a ''piecewise cubic Hermite interpolating polynomial'' (PCHIP). We consider a 3+1 neutrino mixing model with a sterile neutrino having a mass at the eV scale, which can explain the anomalies observed in shortbaseline neutrino oscillation experiments. We find that the freedom of the primordial power spectrum allows to reconcile the cosmological data with a fully thermalized sterile neutrino in the early Universe. Moreover, the cosmological analysis gives us some information on the shape of the primordial power spectrum, which presents a feature around the wavenumber k=0.002 Mpc{sup −1}.},
doi = {10.1088/14757516/2015/04/023},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2015,
place = {United States},
year = 2015,
month = 4
}

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