Constraining an R-parity violating supersymmetric theory from the SuperKamiokande data on atmospheric neutrinos

TL;DR

This paper analyzes how SuperKamiokande atmospheric neutrino data constrains R-parity violating supersymmetric models, finding large allowed parameter regions with minimal fine-tuning, but with restrictions from flavor-changing neutral currents.

Contribution

It provides the first detailed analysis of atmospheric neutrino constraints on bilinear R-parity violating supersymmetry considering both fermionic and scalar sectors.

Findings

Large parameter space allowed without fine-tuning

Additional restrictions from flavor-changing neutral currents

R-violating terms must be smaller or hierarchically arranged

Abstract

The constraints on an R-parity violating supersymmetric theory arising from the recent SuperKamiokande results on atmospheric neutrinos are studied, with special reference to a scenario with bilinear R-parity violating terms. Considering both the fermionic and scalar sectors, we find that a large area of the parameter space is allowed, in terms of both the lepton-number violating entries in the superpotential and the soft R-violating terms in the scalar potential, and that no fine-tuning is required. However, the need to avoid flavour changing neutral currents puts additional restrictions on the theory, requiring either the R-violating terms in the superpotential to be smaller than the R-conserving ones, or a hierarchy in the R-violating parameters for different lepton flavours in the superpotential.