Next-to-leading order QCD corrections to a heavy resonance production and decay into top quark pair at the LHC

We present a complete next-to-leading order (NLO) QCD calculation to a heavy resonance production and decay into a top quark pair at the LHC, where the resonance could be either a Randall-Sundrum (RS) Kaluza-Klein (KK) graviton $G$ or an extra gauge boson $Z'$. The complete NLO QCD corrections can enhance the total cross sections by about $80\%- 100\%$ and $20\%- 40\%$ for the $G$ and the $Z'$, respectively, depending on the resonance mass. We also explore in detail the NLO corrections to the polar angle distributions of the top quark, and our results show that the shapes of the NLO distributions can be different from the leading order (LO) ones for the KK graviton. Moreover, we study the NLO corrections to the spin correlations of the top quark pair production via the above process, and find that the corrections are small.