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e^+ (Anti)Quark Scattering in the Presence of the Anomalous HERA Positron-Jet Event Phenomenon

S. Jadach·W. Placzek·B. F. L. Ward
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Abstract

We discuss the leptoquark interpretation of the anomalous HERA positron-jet events in the context of the YFS exponentiated Monte Carlo event generator treatment of the attendant multiple photon radiative effects for both the would-be signal and the SM background, wherein finite-$p_T$ photon effects are properly taken into account and wherein infrared singularities are cancelled to all orders in $α$. We show that H1 and ZEUS data are consistent with such an interpretation for a leptoquark coupling $\lesssim 0.3g_W$, mass $\sim 200$ GeV, and width $\lesssim 2$GeV. Possible future tests are proposed.

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S. Jadach, W. Placzek, B. F. L. Ward. 1997-05-23. e^+ (Anti)Quark Scattering in the Presence of the Anomalous HERA Positron-Jet Event Phenomenon. https://arxiv.org/abs/hep-ph/9705395

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