Constraints on R-parity violating couplings from CERN LEP and SLAC SLD hadronic observables

We analyze the one loop corrections to hadronic Z decays in an R-parity violating extension to the minimal supersymmetric standard model. Performing a global fit to all the hadronic observables at the Z peak, we obtain stringent constraints on the R-violating coupling constants λ^′ and λ^″. The presence of these couplings worsens the agreement with the data relative to the standard model. The strongest constraints come from the b asymmetry parameters A_b and A_FB(b). From a classical statistical analysis we find that the couplings λ_i31^′, λ_i32^′, and λ₃₂₁^″ are ruled out at the 1σ level, and that λ_i33^′ and λ_33i^″ are ruled out at the 2σ level. A Bayesian statistical analysis weakens the bounds, but the corresponding χ²’s are uncomfortably large, rendering the relevance of the Bayesian bounds suspect.