The ρ-Meson Electromagnetic Form Factors within the Light-Front Quark Model

In this paper, we study the \rho-meson electromagnetic form factors (EMFFs) within the framework of the light-front quark model. The physical form factors G_\rm C,M,Q(Q^2) of the \rho-meson, as well as the charged square radius \langle r^2\rangle, the magnetic moment \mu, and the quadrupole moment \bar Q, are calculated, which describe the behaviors of EMFFs at zero momentum transfer. Using the type-Ⅱ replacement, we find that the zero-mode does contribute zero to the matrix element S_00^+. It is found that the ``M\to M_0" replacement improves the angular condition remarkably, which permits different prescriptions of \rho-meson EMFFs to give the consistent results. The residual tiny violation of angular condition needs other explanations beyond the zero-mode contributions. Our results indicate that the relativistic effects or interaction internal structure are weaken in the zero-binding limit. This work is also applicable to other spin-1 particles.