Updated constraints on non-standard neutrino interactions from Planck

作者：Archidiacono Maria^*; Hannestad Steen

来源：Journal of Cosmology and Astroparticle Physics, 2014, 2014(7): 046.

DOI：10.1088/1475-7516/2014/07/046

• cosmological neutrinos
• particle physics - cosmology connection
• neutrino properties
• physics of the early universe

We provide updated bounds on non-standard neutrino interactions based on data from the Planck satellite as well as auxiliary cosmological measurements. Two types of models are studied - A Fermi-like 4-point interaction and an interaction mediated by a light pseudoscalar - and we show that these two models are representative of models in which neutrinos either decouple or recouple in the early Universe. Current cosmological data constrain the effective 4-point coupling to be G(x) <= (0.06 GeV)(-2), corresponding to G(x) <= 2.5 x 10(7)GF. For non-standard pseudoscalar interactions we set a limit on the diagonal elements of the dimensionless coupling matrix, g(ij), of g(ii) <= 1.2 x 10(-7). For the off-diagonal elements which induce neutrino decay the bound is significantly stronger, corresponding to g(ij) <= 2.3 x 10(-11)(m/0.05 eV)(-2), or a lifetime constraint of iota >= 1.2 x 10(9) s (m/0.05 eV)(3). This is currently the strongest known bound on this particular type of neutrino decay. We finally note that extremely strong neutrino self-interactions which completely suppress anisotropic

• 出版日期2014-7