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arXiv · 1909.08443

Study of interference effects in the search for flavour-changing neutral current interactions involving the top quark and a photon or a $Z$ boson at the LHC

Maura Barros·Nuno Filipe Castro·Johannes Erdmann·Gregor Geßner·Kevin Kröninger·Salvatore La Cagnina·Ana Peixoto
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Abstract

Flavour-changing neutral-current interactions of the top quark can be searched for in top-quark pair production with one top quark decaying to an up-type quark and a neutral boson, and they can be searched for in the single production of a top quark in association with such a boson. Both processes interfere if an additional up-type quark is produced in the case of single production. The impact of these interference effects on searches for flavour-changing neutral currents at the LHC is studied for the case where the neutral boson is a photon or a $Z$ boson. Interference effects are found to be smaller than variations of the renormalisation and factorisation scales.

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Maura Barros, Nuno Filipe Castro, Johannes Erdmann, Gregor Geßner, Kevin Kröninger, Salvatore La Cagnina, Ana Peixoto. 2019-09-18. Study of interference effects in the search for flavour-changing neutral current interactions involving the top quark and a photon or a $Z$ boson at the LHC. https://doi.org/10.1140/epjp/s13360-020-00346-3

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