A light triplet boson and Higgs-to-diphoton in supersymmetric type II seesaw

The supersymmetric type II seesaw may leave a limit where a triplet boson along with the standard Higgs boson remains light. Working in this limit with small triplet vacuum expectation values, we explore how much such a light triplet boson can contribute to the Higgs boson decay to diphoton, and analyze the feasibility to observe it through same-sign di-lepton and tetra-lepton signals in the forthcoming LHC run after setting an LHC7 limit in a simplified parameter space of the triplet vacuum expectation value and the doubly charged boson mass.