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arXiv · hep-ph/9703375

Four-Fermion Effective Interactions and Recent Data at HERA

Nicola Di Bartolomeo·Marco Fabbrichesi
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Abstract

We discuss the possibility of explaining the excess in the cross section at high-Q^2 recently found at HERA in terms of four-fermion effective interactions. To avoid the constraints from low-energy data, we select three special cases in which the contact interaction is a product of vector-vector, axial-axial and vector-axial currents. For these a satisfactory fit of HERA data is possible, while keeping agreement with LEPII and CDF data, for an interaction scale $Λ=3.5$ TeV. As the statistics of the experiments improves-and if the effect persists-it will be soon possible to discriminate between such contact terms and the alternative explanation in terms of leptoquark exchange.

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Nicola Di Bartolomeo, Marco Fabbrichesi. 1997-05-13. Four-Fermion Effective Interactions and Recent Data at HERA. https://doi.org/10.1016/s0370-2693(97)00678-3

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