Description
Electromagnetic form factors of spin 0 and spin 1/2 particles are fundamental quantities related to the charge and magnetization distribution inside the particle. Understanding the electromagnetic structure of particles in the terms of their correct parameterization as electromagnetic form factors and uncertainties help us to study the data from polarized or unpolarized scattering and annihilation experiments. In the recent time the Unitary & Analytic model was successfully applied for various problems in the field of phenomenology of particle physics.
In this contribution I summarize the role of pion form factor in the search for dumped oscillating structures, additionally the charged and neutral kaons in the calculation of charge radii, the correction to the Dashen’s theorem and contributions of the box diagrams for the light-by-light scattering, in order to reveal to what extent the unreliable experimental behaviours of the corresponding electromagnetic form factors in the space-like region influenced the calculated physical quantities. I also mention the results of evaluation of proton charge radius and possible existence of zero in proton elastic form factor.