Researchers have calculated the electromagnetic form factors of the ρ (rho) meson at one loop within the framework of Chiral Perturbation Theory (χPT). This work represents an advancement in understanding the internal structure of hadrons, particles composed of quarks and gluons, and how they interact with the electromagnetic field. χPT is an effective tool for describing the dynamics of light mesons at low energies, where quantum chromodynamics (QCD) is non-perturbative.

The calculation specifically addresses power-counting-violating terms in loop diagrams, using infrared regularization for their subtraction. Furthermore, Ward identities were explicitly verified at the order considered, ensuring the consistency of the results with the conservation principles of quantum field theory. These form factors are crucial for determining the charge and current distribution within the ρ meson, providing insights into its size and shape.

The obtained results are compared with recent calculations performed within the framework of non-relativistic effective field theory. This comparison is fundamental for validating consistency between different theoretical approximations and for refining our understanding of vectorial meson properties. The precision of these calculations is vital for future interpretations of experimental data in particle physics, especially in experiments involving meson production and decay.