Electromagnetic rho-meson form factors in point-form relativistic quantum mechanics

Understand

The relativistic point-form formalism that we proposed for the study of the electroweak structure of few-body bound states is applied to calculate the elastic form factors of spin-1 mesons, such as the rho meson, within constituent-quark models.

• We treat electron-meson scattering as a Poincare-invariant coupled-channel problem for a Bakamjian-Thomas mass operator and extract the meson current from the resulting invariant 1-photon-exchange amplitude.
• Wrong cluster properties inherent in the Bakamjian-Thomas framework are seen to cause spurious contributions in the current.
• These contributions, however, can be separated unambiguously from the physical ones and we end up with a meson current with all required properties.