WHAT HEAVY QUANTA BOUNDS COULD BE INFERRED FROM A HIGGS DISCOVERY?

Abstract

The Higgs-gauge bosons couplings ghVV(V = g, γ, W, Z) receive non-decoupling corrections due to heavy quanta, and deviations from the SM predictions can be used to test its presence. The possible Higgs signal recently reported at LEP, with mh = 115 GeV , severely constrains the presence of heavy quanta, such as a heavy fourth family. At Tevatron, the Higgs production by gluon fusion, followed by the decay h → WW*, can also be used to probe the existence of heavy colored particles, including additional standard or mirror families, chiral colored sextets and octet quarks. Within the MSSM, we also find that gluon fusion is a sensitive probe for the spectrum of squark masses.