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R Parity in Standard--like Superstring Models

Edi Halyo
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Abstract

We investigate the R symmetries of standard--like superstring models. At the level of the cubic superpotential there are three global $U(1)$ R symmetries. These are broken explicitly by $N>3$ terms in the superpotential and spontaneously by scalar VEVs necessary to preserve supersymmetry at $M_P$. A $Z_2$ discrete symmetry remains but is equivalent to fermion number modulo 2. These models possess an effective R parity which arises from the interplay between the gauged $U(1)_{B-L}$ and $U(1)_{r_{j+3}}$.

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Edi Halyo. 1994-02-03. R Parity in Standard--like Superstring Models. https://doi.org/10.1142/s0217732394001246

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