Tree-level unitarity violation for large Higgs mass in a supersymmetric extension of the standard model

Abstract

In a minimal supersymmetric extension of the standard model we calculate the critical Higgs mass for violation of tree-level unitarity in scattering processes involving intermediate vector bosons and Higgs and their supersymmetric partners. We also calculate the critical energy for violation of tree-level unitary in the limit of very large Higgs mass. We find, within this minimal model, that both bosonic and fermionic processes in certain definite channels simultaneously violate, at large s, tree-level unitarity beyond a critical value of the Higgs mass of the order of 770 GeV, rather lower than the corresponding critical mass, 1 TeV, for which violation is expected in the standard model. Also, when taking the large Higgs mass limit and going to large s, we find that tree-level unitarity gets violated at a critical energy s c of the order of 1 TeV, again lower than the corresponding value for the standard model (∼1.7 TeV).