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arXiv · hep-ex/9903072

Search for Leptoquarks and FCNC in e^+ e^- annihilations at $\sqrt{s}=183 GeV$

DELPHI Collaboration·P. Abreu et al
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Abstract

A search for events with one jet and at most one isolated lepton used data taken at LEP-2 by the DELPHI detector.These data were accumulated at a center-of-mass energy of 183 GeV and correspond to an integrated luminosity of 47.7 1/pb. Production of single scalar and vector leptoquarks was searched for. Limits at 95% confidence level were derived on the masses (ranging from $134 GeV/c^2$ to $171 GeV/c^2$ for electromagnetic type couplings) and couplings of the leptoquark states.A search for top-charm flavour changing neutral currents($e^+ e^- \to \bar t c$ or charge conjugate) used the semileptonic decay channel. A limit on the flavour changing cross-section via neutral currents was set at 0.55pb (95% confidence level).

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DELPHI Collaboration, P. Abreu et al. 1999-03-31. Search for Leptoquarks and FCNC in e^+ e^- annihilations at $\sqrt{s}=183 GeV$. https://doi.org/10.1016/s0370-2693(98)01525-1

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