Precision calculations for $h \to WW/ZZ \to 4$ fermions in a Singlet Extension of the Standard Model with Prophecy4f

Understand

We consider an extension of the Standard Model by a real singlet scalar field with a $Z_2$-symmetric Lagrangian and spontaneous symmetry breaking with vacuum expectation value for the singlet.

• Considering the lighter of the two scalars of the theory to be the 125GeV Higgs particle, we parametrize the scalar sector by the mass of the heavy Higgs boson, a mixing angle $\alpha$, and a scalar Higgs self-coupling $\lambda_{12}$.
• Taking into account theoretical constraints from perturbativity and vacuum stability, we compute next-to-leading-order electroweak and QCD corrections to the decays $h\to WW/ZZ \to 4$ fermions of the light Higgs boson for some scenarios proposed in the literature.
• We formulate two renormalization schemes and investigate the conversion of the input parameters between the schemes, finding sizeable effects.