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arXiv · 1009.0905

A unique Z_4^R symmetry for the MSSM

Hyun Min Lee·Stuart Raby·Michael Ratz·Graham G. Ross·Roland Schieren·Kai Schmidt-Hoberg·Patrick K. S. Vaudrevange
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Abstract

We consider the possible anomaly free Abelian discrete symmetries of the MSSM that forbid the mu-term at perturbative order. Allowing for anomaly cancellation via the Green-Schwarz mechanism we identify discrete R-symmetries as the only possibility and prove that there is a unique Z_4^R symmetry that commutes with SO(10). We argue that non-perturbative effects will generate a mu-term of electroweak order thus solving the mu-problem. The non-perturbative effects break the Z_4^R symmetry leaving an exact Z_2 matter parity. As a result dimension four baryon- and lepton-number violating operators are absent while, at the non-perturbative level, dimension five baryon- and lepton-number violating operators get induced but are highly suppressed so that the nucleon decay rate is well within present bounds.

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Hyun Min Lee, Stuart Raby, Michael Ratz, Graham G. Ross, Roland Schieren, Kai Schmidt-Hoberg, Patrick K. S. Vaudrevange. 2010-09-28. A unique Z_4^R symmetry for the MSSM. https://doi.org/10.1016/j.physletb.2010.10.038

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