Effects of CP-violating phases on Higgs boson production at hadron colliders in the minimal supersymmetric standard model

If the soft Supersymmetry (SUSY) breaking masses and couplings are complex, then the associated CP-violating phases can in principle modify the known phenomenological pattern of the Minimal Supersymmetric Standard Model (MSSM). We investigate here their effects on Higgs boson production in the gluon-gluon fusion mode at the Tevatron and the Large Hadron Collider (LHC), by taking into account all experimental bounds available at present. The by far most stringent ones are those derived from the measurements of the Electric Dipole Moments (EDMs) of fermions. However, it has recently been suggested that, over a sizable portion of the MSSM parameter space, cancellations among the SUSY contributions to the EDMs can take place, so that the CP-violating phases can evade those limits. We find a strong dependence of the production rates of any neutral Higgs state upon the complex masses and couplings over such parts of the MSSM parameter space. We show these effects relatively to the ordinary MSSM rates as well as illustrate them at absolute cross section level at both colliders. (C) 2000 Elsevier Science B,V. All rights reserved.