The Non-Perturbative Scalar Yukawa Theory on the Light Front

We present a non-perturbative calculation of the scalar Yukawa model in light-front dynamics with a Fock sector dependent renormalization. The Fock space is truncated to four particles and then the \textit{ab initio} Hamiltonian approach is applied. We compute the electromagnetic form factor and compare it with the results obtained from the lower Fock sector truncations. We find that the one- and two-body contributions dominate the Fock space even in the non-perturbative region. However, the four-body contribution exceeds the three-body one as the coupling constant increases. Nevertheless, the form factor shows a good converge as the number of constituent bosons increases.