A complete next-to-leading order QCD description of resonant $Z'$ production and decay into $t\bar t$ final states

Understand

We discuss QCD radiative corrections to the production of a heavy neutral resonance $Z'$ at the LHC assuming that it decays into a $ t\bar t$ final state.

• Compared to previous studies, our computation includes top quark decays as well as interference between the $Z'$ signal process and the QCD $t \bar t$ background.
• The interference contribution appears for the first time at next-to-leading order (NLO) QCD and requires new one-loop amplitudes that are not present when signal and background are treated separately.
• We describe some examples of how QCD radiative corrections may influence both the exclusion limits and studies of properties of the new resonance, once it is discovered.