On the relationship between the deuteron form factors and the physical $S$-matrix. II

An expression is found for the form factors of the matrix element of the electromagnetic current of the neutron-proton system in terms of the relativistic Jost matrix. To this end the relativistic parametrization of the neutron-proton system obtained in [1] is used directly. The contribution of the anomalous cut is taken into account fully. No allowance is made for effects due to meson current and inelastic $n-p$-channels. The results obtained are needed to express the electromagnetic form factors of the deuteron in terms of the neutron-proton $S$-matrix on the mass shell.