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A Stable Proton without R-Parity--Implications for the LSP--

Radu Tatar·Taizan Watari
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Abstract

The proton decays too rapidly in supersymmetric theories if a dimension-4 operator \bar{5}.10.\bar{5} exists in the superpotential. The conventional idea is to impose the R-parity to kill this operator with a stable lightest supersymmetry particle (LSP) as a direct consequence. However, the SUSY-zero mechanism is also able to kill the operator without an unbroken R-parity. In this article, we provide a firm theoretical justification for the absence of the dimension-4 proton decay operator under the SUSY-zero mechanism, by using some input from string theory. The LSP may be unstable without the R-parity and, indeed, some dimension-5 R-parity violating operators may be generated in effective theories. This suggests that the dark matter is an axion in this string theory inspired model. An insight on the SUSY-zero mechanism is also obtained.

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Radu Tatar, Taizan Watari. 2006-05-29. A Stable Proton without R-Parity--Implications for the LSP--. https://doi.org/10.1016/j.physletb.2007.01.020

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