High Q(2) physics at HERA and searches for new particles

Preliminary results from H1 and ZEUS on e(+)p scattering at high momentum t ransfer squared, Q(2), are presented, using all available data accumulated by the H1 and ZEUS experiments between 1994-97, corresponding to integrated luminosities of 37 pb(-1) and 47 pb(-1), respectively. The anomalies obser ved at high Q(2) in the 1994-96 data remain, though with less significance. Since this high Q(2) domain represents a new frontier in deep inelastic sc attering (DIS), these data are used to search for new particles possessing direct couplings to lepton-quark pairs. Assuming that the slight excess of events observed in neutral current DIS is due to a statistical fluctuation, preliminary limits on the production of leptoquarks and of squarks in R-pa rity violating the minimal supersymmetric standard model are presented.