Scalar particle contribution to Higgs production via gluon fusion at NLO

Abstract

We consider the gluon fusion production cross section of a scalar Higgs boson in models where fermion and scalar massive colored particles are present. We report analytic expressions for the matrix elements of gg -> Hg, q(q)[overline] -> Hg, and qg -> Hq processes completing the calculation of the NLO QCD corrections in these extended scenarios. The formulas are written in a complete general case, allowing a flexible use for different theoretical models. Applications of our results to two different models are presented: i) a model in which the SM Higgs sector is augmented by a weak doublet scalar in the SU(Nc) adjoint representation. ii) The MSSM, in the limit of neglecting the gluino contribution to the cross section.