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Flavour and polarisation in heavy neutrino production at e+ e- colliders

F. del Aguila·J. A. Aguilar-Saavedra·A. Martinez de la Ossa·D. Meloni
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Abstract

We analyse l W nu production at ILC, paying special attention to the role of the final lepton flavour and beam polarisation in the search for a new heavy neutrino N. We show that a sizeable coupling to the electron V_eN ~ 10^-2 is necessary to have an observable signal in any of the channels, despite the fact that the signal may be more visible in muon or tau final states. The non-observation of a heavy neutrino at ILC will improve the present upper bound on its mixing with the electron by more than one order of magnitude, V_eN < 0.007 for m_N between 200 and 400 GeV.

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F. del Aguila, J. A. Aguilar-Saavedra, A. Martinez de la Ossa, D. Meloni. 2005-03-22. Flavour and polarisation in heavy neutrino production at e+ e- colliders. https://doi.org/10.1016/j.physletb.2005.03.054

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