Hint of non-standard dynamics in solar neutrino conversion

Abstract

Motivated by the recent low-threshold measurements of the solar 8B neutrino spectrum performed by Borexino, Super-Kamiokande and the Sudbury Neutrino Observatory -- all now monitoring the transition regime between low-energy (vacuum-like) and high-energy (matter-dominated) flavor conversions -- we consider the role of sub-dominant dynamical terms induced by new flavor-changing interactions. We find that the presence of such perturbations with strength ~ 0.1 G_F is now favored, offering a better description of the anomalous behavior suggested by the new results, whose spectrum shows no sign of the typical low-energy upturn predicted by the standard MSW mechanism. Our findings, if interpreted in a 2-flavor scheme, provide a hint of such new interactions at the ~ 2 sigma level, which is rather robust with respect to 3-flavor effects possibly induced by non-zero theta_13.

5 pages, 4 figures; one figure added; minor changes in the text; references added; matches version published in PRD (Rapid Communications)

References in corpus (5)

• Phenomenology with Massive Neutrinos
• General bounds on non-standard neutrino interactions
• Interpretation of MINOS data in terms of non-standard neutrino interactions
• Contrasting solar and reactor neutrinos with a non-zero value of theta13
• Apparent multiple Delta m^2_32 in muon anti-neutrino and muon neutrino survival oscillations from non-standard interaction matter effect

Cited by in corpus (9)

• Updated fit to three neutrino mixing: status of leptonic CP violation
• Status of non-standard neutrino interactions
• Degeneracy between ${\theta }_{23}$ octant and neutrino non-standard interactions at DUNE
• Neutrino oscillations: the rise of the PMNS paradigm
• Testing the very-short-baseline neutrino anomalies at the solar sector
• Solar neutrino physics with low-threshold dark matter detectors
• Neutrino oscillations and Non-Standard Interactions
• Searching for Axial Neutral Current Non-Standard Interactions of neutrinos by DUNE-like experiments
• Non-standard interactions from the future neutrino solar sector