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LEP- and low energy-bounds on R-parity-violating supersymmetric Yukawa couplings

Gautam Bhattacharyya
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Abstract

Electroweak precision data at LEP are used to place bounds on some $λ'$-type ($L$-violating) and $λ''$-type ($B$-violating) $R$-parity violating supersymmetric Yukawa couplings. We consider one-loop corrections (triangles and self-energies) induced by these couplings to the $Z$-partial widths. The couplings involving the top quark induce stronger loop effects and hence are more strongly constrained than others. On the other hand, information on $D$- and $τ$-decays are used to constrain some of the $λ'$-type couplings which are complementary to the ones constrained from LEP. Among the bounds we have derived, many are new from a phenomenological view-point.

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Gautam Bhattacharyya. 1995-11-29. LEP- and low energy-bounds on R-parity-violating supersymmetric Yukawa couplings. https://arxiv.org/abs/hep-ph/9511447

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