Confinement in the tricritical Ising model

We study the leading and sub-leading magnetic perturbations of thermal $E_7$ integrable deformation tricritical Ising model. In low-temperature phase, these lead to confinement kinks The resulting meson spectrum can be obtained using semi-classical quantisation, here extended include also mesonic excitations composed two different kinks. An interesting feature perturbation model is possibility swap role operators, i.e. consider as a $\mathcal{A}_3$ associated deformation. Due occurrence vacuum degeneracy unrelated spontaneous symmetry breaking in $\mathcal{A}_3$, pattern shows novel features compared previously studied models. Interestingly enough, validity description terms endpoint extends well beyond small fields, therefore full parameter space joint described by combination approaches. All predictions are verified comparison finite volume from truncated conformal space.