Pseudo-scalar Higgs boson production at threshold N3LO and N3LL QCD

We present the first results on the production of pseudo-scalar Higgs boson through gluon fusion at the LHC to N3LO in QCD taking into account only soft-gluon effects. We have used the effective Lagrangian that describes the coupling of the pseudo-scalar Higgs boson with the gluons in the large top quark mass limit. We have used quantities that have recently become available, namely the three-loop pseudo-scalar Higgs boson form factor and the third order universal soft function in QCD to achieve this. Along with the fixed order results, we also present the process dependent resummation coefficient for a threshold resummation to N3LL in QCD. Phenomenological impact of these threshold N3LO corrections to pseudo-scalar Higgs boson production at the LHC is presented and their role in the reduction of the renormalization scale dependence is demonstrated.