A search for squarks of Rp-violating SUSY at HERA

A search for squarks ofR-parity violating supersymmetry is performed inep collisions at HERAusing H1 1994e + data. Direct single production of squarks of each generation bye +-quark fusion via a Yukawa coupling λ′ is considered. All possibleR-parity violating decays and gauge decays of the squarks are taken into account. No significant deviation from the Standard Modelpredictions is found in the various multi-lepton and multi-jet final states studied and exclusion limits are derived. At 95% confidence level, the existence of first generation squarks is excludedfor masses up to 240 GeV for coupling values λ′≳√4πα em. The limits obtained are shown to be only weakly dependent on the free parametersof the Minimal Supersymmetric Standard Model. Stop squarksare excludedfor masses up to 138 GeV for coupling λ′×cosθ t toe +d pairs ≳0.1×√4πα em, whereθ t is the mass mixing angle.