Virtual corrections to gg -> H to two loops in the heavy top limit

The virtual corrections to the production cross section of a Standard Model Higgs boson are computed up to order alpha (4)(s). Using an effective Lagr angian for the limit M-t --> infinity, we evaluate the relevant massless tw o-loop vertex diagrams by mapping them onto three-loop two-point functions, following a method recently introduced by Baikov and Smirnov [1]. As a res ult, we find a gauge-invariant contribution to the total Higgs production c ross section at NNLO. (C) 2000 Elsevier Science B.V. All rights reserved.