Is cosmology compatible with sterile neutrinos?

Journal Article · Tue Nov 01 04:00:00 EST 2005 · Phys.Rev.Lett.97:04301,2006

OSTI ID:879043

Dodelson, Scott; Melchiorri, Alessandro; Slosar, Anze

By combining data from cosmic microwave background (CMB) experiments (including the recent BOOMERANG-2K2 results), large scale structure (LSS) and Lyman-{alpha} forest observations, we constrain the hypothesis of a fourth, sterile, massive neutrino. For the 3 massless + 1 massive neutrino case we bound the mass of the sterile neutrino to m{sub s} < 0.55eV at 95% c.l.. These results exclude at high significance the sterile neutrino hypothesis as an explanation of the LSND anomaly. We then generalize the analysis to account for active neutrino masses (which tightens the limit to m{sub s} < 0.51eV) and the possibility that the sterile abundance is not thermal. In the latter case, the constraints in the (mass, density) plane are non-trivial. For a mass of > 1eV or < 0.05eV the cosmological energy density in sterile neutrinos is always constrained to be {omega}{sub {nu}} < 0.005 at 95% c.l.. However, for a sterile neutrino mass of {approx} 0.25 eV, {omega}{sub {nu}} can be as large as 0.015.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 879043
• Report Number(s): FERMILAB-PUB-05-585-A; arXiv eprint number astro-ph/0511500
• Journal Information: Phys.Rev.Lett.97:04301,2006, Journal Name: Phys.Rev.Lett.97:04301,2006
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ABUNDANCE
Astrophysics
COSMOLOGY
ENERGY DENSITY
FORESTS
HYPOTHESIS
NEUTRINOS
RELICT RADIATION