Abstract
The gauge-extended U(1)C×SU(2)L×U(1)IR×U(1)L model elevates the global symmetries of the standard model (baryon number B and lepton number L) to local gauge symmetries. The U(1)L symmetry leads to three superweakly interacting right-handed neutrinos. This also renders a B-L symmetry nonanomalous. The superweak interactions of these Dirac states permit νR decoupling just above the QCD phase transition: 175≲TνRdec/MeV≲250. In this transitional region, the residual temperature ratio between νL and νR generates extra relativistic degrees of freedom at BBN and at the CMB epochs. Consistency with both WMAP 7-year data and recent estimates of the primordial 4He mass fraction is achieved for 3B-L/TeV
Keywords
local gauge symmetries
Subject Categories
Cosmology, Neutrinos
Disciplines
Physics
Publisher
American Physical Society
Publication Date
2-23-2012
Rights Information
Copyright (2012) American Physical Society
Rights Holder
American Physical Society
Recommended Citation
Anchordoqui, Luis Alfredo and Goldberg, Haim, "Neutrino Cosmology after WMAP 7-year data and LHC first Z′ bounds" (2012). Physics Faculty Publications. Paper 517.
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Notes
Originally published in Physical Review Letters v.108 (2012): 081805. DOI: http://link.aps.org/doi/10.1103/PhysRevLett.108.081805”> 10.1103/PhysRevLett.108.081805.