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Standard and Non-Standard Physics in Neutrino Oscillations

M. Maltoni
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Abstract

We analyze the impact of recent solar and atmospheric data in the determination of the neutrino oscillation parameters, taking into account that both the solar nu_e and the atmospheric nu_mu may convert to a mixture of active and sterile neutrinos. Furthermore, in the context of the atmospheric neutrino problem we discuss an extended mechanism of neutrino propagation which combines both oscillations and non-standard neutrino-matter interactions. We use the most recent neutrino data, including the 1496-day Super-K solar and atmospheric data samples, the latest SNO spectral and day/night solar data, and the final MACRO atmospheric results. We confirm the clear preference of all the data for pure-active oscillation solutions, bounding the fraction of sterile neutrino involved in oscillations to be less than 52% in the solar sector and less than 40% in the atmospheric sector, at 3 sigma. For the atmospheric case we also derive a bound on the total amount of non-standard neutrino-matter interactions, bounding the flavor-changing component to -0.03 <= epsilon <= 0.02 and the non-universal component to |epsilon'| <= 0.05.

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M. Maltoni. 2002-10-07. Standard and Non-Standard Physics in Neutrino Oscillations. https://doi.org/10.1016/s0920-5632(02)01904-7

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