Unitarity constraints in triplet extensions beyond the large s limit

Understand

Triplet extensions are attractive alternatives to the standard model (SM) of particle physics.

• While models with only one triplet are highly constrained by electroweak precision observables, this is not necessarily the case once several triplets are present as in the Georgi-Machacek model.
• As in all other BSM models, the parameter space of triplet extensions is constrained by the condition that perturbative unitarity is not violated.
• For this purpose, limits on the eigenvalues of the scalar $2 \to 2$ scattering matrix are set.