Charged Higgs boson phenomenology in supersymmetric models with Higgs triplets

We present a detailed study of the Higgs sector within an extension of the minimal supersymmetric standard model that includes one complex Higgs triplet (MSSM+1CHT). The model spectrum includes three singly charged Higgs bosons as well as three CP-even (or scalar) and two CP-odd (or pseudoscalar) neutral Higgs bosons. We present an approximated calculation of the one-loop radiative corrections to the neutral CP-even Higgs masses (m_Hi⁰) and the couplings H_i⁰Z⁰Z⁰ (i=1, 2, 3), which determine the magnitude of the Higgs-strahlung processes e⁺e^-→Z⁰H_i⁰. Limits from LEP2 are then considered, in order to obtain bounds on the neutral Higgs sector. Further, we also include the experimental limits from LEP2 on e⁺e^-→H⁺H^- and those on BR(t→bH⁺) from Tevatron, to derive bounds on the mass of the two lightest charged Higgs bosons (H₁^± and H₂^±). Concerning the latter, we find some cases, where m_H1^±≃90  GeV, that are not excluded by any experimental bound, even for large values of tan⁡β, so that they should be looked for at the Large Hadron Collider (LHC).