Singlet Extension of the Standard Model

In this work the Standard Model Higgs sector is extended by means of a real singlet field. Then the elements necessary to develop one-loop level evaluation are built. Tadpole removal, diagonalization of the neutral sector and renormalization are achieved for the extended model, then the partial decay widths of the two Higgs into vector bosons W and Z are evaluated. The resulting expressions have been used for a numerical evaluation of the heavy Higgs partial widths, and are reported in the work.