Charge Radius of Pion

Using a dispersion relation for Compton scattering of virtual photons on pions, the charge radius of the pion is analyzed in terms of ${\pi }^{\pm }-{\pi }^0$ mass difference. It is found to be of the order of magnitude 0.46×${10}^{-13\mathrm{}}$ cm-0.56×${10}^{-13\mathrm{}}$ cm.