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Dimension-Five Operators in Grand Unified Theories

Joshua Sayre·Soren Wiesenfeldt·Scott Willenbrock
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Abstract

Extensions of the standard model with low-energy supersymmetry generically allow baryon- and lepton-number violating operators of dimension four and five, yielding rapid proton decay. The dimension-four operators are usually forbidden by matter parity. We investigate to what extent the appearance of dimension-five operators at the Planck scale may be constrained by the different grand-unified gauge groups. Dimension-five operators are suppressed in models based on E_6 and SU(3)_C x SU(3)_L x SU(3)_R, where four matter fields do not form a gauge singlet. An intermediate scale offers the possibility to sufficiently suppress these dimension-five operators.

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Joshua Sayre, Soren Wiesenfeldt, Scott Willenbrock. 2007-02-13. Dimension-Five Operators in Grand Unified Theories. https://doi.org/10.1103/physrevd.75.037702

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