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LHC and lepton flavour violation phenomenology of a left-right extension of the MSSM. (English) Zbl 1294.81337

Summary: We study the phenomenology of a supersymmetric left-right model, assuming minimal supergravity boundary conditions. Both left-right and (B-L) symmetries are broken at an energy scale close to, but significantly below the GUT scale. Neutrino data is explained via a seesaw mechanism. We calculate the RGEs for superpotential and soft parameters complete at 2-loop order. At low energies lepton flavour violation (LFV) and small, but potentially measurable mass splittings in the charged scalar lepton sector appear, due to the RGE running. Different from the supersymmetric “pure seesaw” models, both, LFV and slepton mass splittings, occur not only in the left-but also in the right slepton sector. Especially, ratios of LFV slepton decays, such as \({{{{\text{Br}}\left( {{{\tilde{\tau}}_R} \to \mu \chi_1^0} \right)}} \left/ {{{\text{Br}}\left( {{{\tilde{\tau}}_L} \to \mu \chi_1^0} \right)}} \right.}\) are sensitive to the ratio of (B-L) and left-right symmetry breaking scales. Also the model predicts a polarization asymmetry of the outgoing positrons in the decay \({\mu}^{+} \to e^{+}{\gamma}\), \(\mathcal{A} \sim \left[ {0,1} \right] \), which differs from the pure seesaw “prediction” \(\mathcal{A} = 1\). Observation of any of these signals allows to distinguish this model from any of the three standard, pure (mSugra) seesaw setups.

MSC:

81V22 Unified quantum theories
81T60 Supersymmetric field theories in quantum mechanics
81V15 Weak interaction in quantum theory
81V17 Gravitational interaction in quantum theory
81T17 Renormalization group methods applied to problems in quantum field theory
83E50 Supergravity
81R40 Symmetry breaking in quantum theory
81T15 Perturbative methods of renormalization applied to problems in quantum field theory

Software:

SARAH; Spheno
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References:

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