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arXiv · hep-ph/9408230

Discrete symmetries and isosinglet quarks in low-energy supersymmetry

Diego J. Castano·Stephen P. Martin
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Abstract

Many extensions of the minimal supersymmetric standard model contain superfields for quarks which are singlets under weak isospin with electric charge -1/3. We explore the possibility that such isosinglet quarks have low or intermediate scale masses, but do not mediate rapid proton decay because of a discrete symmetry. By imposing the discrete gauge anomaly cancellation conditions, we show that the simplest way to achieve this is to extend the Z_3 "baryon parity" of Ibanez and Ross to the isosinglet quark superfields. This can be done in three distinct ways. This strategy is not consistent with grand unification with a simple gauge group, but may find a natural place in superstring-inspired models, for example. An interesting feature of this scenario is that proton decay is absolutely forbidden.

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Diego J. Castano, Stephen P. Martin. 1994-08-04. Discrete symmetries and isosinglet quarks in low-energy supersymmetry. https://doi.org/10.1016/0370-2693(94)91299-8

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