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arXiv · hep-ph/9803308

Hierarchies of R-violating interactions from Family Symmetries

John Ellis·Smaragda Lola·Graham G. Ross
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Abstract

We investigate the possibility of constructing models of R-violating LQD Yukawa couplings using a single U(1) flavour-symmetry group and supermultiplet charge assignments that are compatible with the known hierarchies of quark and lepton masses. The mismatch of mass and current eigenstates inferred from the known charged-current mixing induces the propagation of strong phenomenological constraints on some R-violating couplings to many others. Applying these constraints, we look for flavour-symmetry models that are consistent with different squark-production hypotheses devised to explain the possible HERA large-Q^2 anomaly. The e^+ d -> stop interpretation of the HERA data is accommodated relatively easily, at the price of postulating an extra parity. The e^+ s -> stop interpretation of the events requires models to have only small (2,3) mixing in the down quark sector. The e^+ d -> scharm mechanism cannot be accommodated without large violations of squark-mass universality, due to the very strong experimental constraints on R-violating operators. We display a model in which baryon decay due to dangerous dimension-five operators is automatically suppressed.

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John Ellis, Smaragda Lola, Graham G. Ross. 1998-03-11. Hierarchies of R-violating interactions from Family Symmetries. https://doi.org/10.1016/s0550-3213(98)00423-4

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