BOUNDS FROM T(T)OVER-BAR PRODUCTION ON R-PARITY VIOLATING MODELS OF SUPERSYMMETRY

We study t (t) over bar production in R-parity violating supersymmetry . The annihilation channel q (q) over bar --> t (t) over bar gets new contributions from t-channel exchange of squarks or sleptons. With the data from Tevatron on t (t) over bar production, we find that the squ ark- or slepton-exchange processes constrain the B-violating lambda'' couplings or the L-violating lambda' couplings, respectively. In the r elevant region of the MSSM parameter space, our bounds are already com parable to the few existing constraints on third-generation R-parity v iolating couplings, and will improve when more precise measurements of the ii production cross section become available. We also discuss the effects of these couplings for top production at the LHC. (C) 1997 Pu blished by Elsevier Science B.V.