Probing long-range leptonic forces with solar and reactor neutrinos

Abstract

In this work we study the phenomenological consequences of the existence of long-rangeforces coupled to lepton flavour numbers in solar neutrino oscillations. We study electronicforces mediated by scalar, vector or tensor neutral bosons and analyse their effect on thepropagation of solar neutrinos as a function of the force strength and range. Under theassumption of one mass scale dominance, we perform a global analysis of solar andKamLAND neutrino data which depends on the two standard oscillation parameters,Δm212 and tan2 θ12, the force coupling constant, its range and, for the case of scalar-mediatedinteractions, on the neutrino mass scale as well. We find that, generically, theinclusion of the new interaction does not lead to a very statistically significantimprovement on the description of the data in the most favored MSW LMA(or LMA-I) region. It does, however, substantially improve the fit in thehigh-Δm2 LMA (or LMA-II) region which can be allowed for vector and scalarlepto-forces (in this last case if neutrinos are very hierarchical) at 2.5σ. Conversely, the analysis allows us to place stringent constraints on the strength versusrange of the leptonic interaction.