On top quark mass effects to gg → ZH at NLO

We compute next-to-leading order QCD corrections to the process gg → ZH. In the effective-theory approach we confirm the results in the literature. We consider top quark mass corrections via an asymptotic expansion and show that there is a good convergence below the top quark threshold which describes approximately a quarter of the total cross section. Our corrections are implemented in the publicly available C++ program ggzh.