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An excess of events at large Q2 with a positron in the final state has been observed at HERA which, if confirmed, would be a signal of new physics. It is not clear at present if a signal of comparable rate is also seen in the charged current channel (with an antineutrino in the final state). In this note we analyse the implications of the presence of such a signal in models of new physics based on contact terms, leptoquarks and squarks with R-violating decays. We find that in all cases the most likely possibility is that the charged current signal is absent. As a consequence if this signal is present the resulting indications are very selective. In particular for squarks only charged current events with multi-quark final states are possible with quite definite predictions on the spectrum of supersymmetric particles.
A light stop, with an R-parity-violating coupling $lambda_{131}$, has been suggested as an explanation of the excess in high-$Q^2$ neutral current events observed at the HERA collider. We show that in this scheme a corresponding excess in charged cur
High-Q^2 NC and CC DIS cross sections have been measured by H1 and ZEUS at HERA. Both NC and CC results based on data taken during the year 1994-2000 are in good agreement with Standard Model expectations. The structure function xF_3 is extracted fro
Charm production in charged current deep inelastic scattering has been measured for the first time in $e^{pm}p$ collisions, using data collected with the ZEUS detector at HERA, corresponding to an integrated luminosity of $358 pb^{-1}$. Results are p
We explore interpretations of the anomaly observed by H1 and ZEUS at HERA in deep-inelastic e^+ p scattering at very large Q^2. We discuss the possibilities of new effective interactions and the production of a narrow state of mass 200 GeV with lepto
A recent H1 measurement of triple differential dijet cross sections in electron-proton interactions in the region of photon virtualities 2<Q2<80 GeV is presented and compared to LO and NLO QCD predictions. Effects that go beyond the fixed-order NLO QCD calculations are identified.