Tracking down Higgs scalars with enhanced couplings

Electroweak models with two doublets of Higgs scalar bosons have theoretical and possibly experimental motivations. With two doublets, one finds that the couplings of the Higgs scalars are modified and strong enhancements are possible. Such enhancements can have a variety of important consequences if there exists a light neutral Higgs scalar (mass $t$-quark mass. The two-gluon decay mode of this Higgs boson can become predominant, and decays into two muons can be quite suppressed. We show here the complete one-loop induced effective Hamiltonian for the decay of the $b$ quark into a Higgs boson ($b\to \mathrm{Higgs}\mathrm{ }\mathrm{boson}+s$); the resulting phenomenology is strongly affected by enhanced couplings. Consequences for supersymmetry are also discussed.