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

Abstract In this paper, we study the ρ-meson electromagnetic form factors (EMFFs) within the framework of the light-front quark model. The physical form factors G_C,M,Q(Q²) of the ρ-meson, as well as the charged square radius 〈r²〉, the magnetic moment μ, and the quadrupole moment $\overline{Q}$, 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 → M₀” replacement improves the angular condition remarkably, which permits different prescriptions of ρ-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.