Interaction constants of vector mesons with the nucleon in the vector-dominance model

The determination of accurate values of the vector and tensor coupling constants of the vector meson with the nucleon, as in the case of the coupling constant of the photon with the vector meson, is important for many theoretical models of hadronic and nuclear physics. A vector-dominance model (VDM) is traditionally considered as the simplest path to the determination of these constants from the data on electron-proton scattering. The fit of the predicted VDM expressions for the Dirac and Pauli form factors of the nucleon, to the data in the region of low values of the squared 4-momentium transfer, Q2≤1GeV2, allows one to estimate with good accuracy the coupling constants. However, in an extended VDM including at least three isoscalar and three isovector mesons, not only the interaction constants, but also the meson masses are usually considered as free parameters of the model. As a consequence of this, the values of the coupling constants essentially depend on the number and masses of the vector mesons