Charge splitting in $\pi N\mathrm{\Delta }$ formfactor

Experimental data on $\pi N$ scattering in the elastic energy region $W \leq 1.45 GeV $areanalyzedwithinthe$K$-matrix approach with effective Lagrangians. The charge splitting in ${\delta }_{33}^{++}$ and ${\delta }_{33}^0$ phases obtaned in the phase shift analisys is studed . It is shown that the change in the sign in the energy dependence of the phase difference can be obtained with different formfactors of the ${\mathrm{\Delta }}^{++}$ and ${\mathrm{\Delta }}^0$ only . This means that ${\mathrm{\Delta }}^{++}$ and ${\mathrm{\Delta }}^0$ has a different size in $\pi N$ interaction.The underlying nature of the observed phenomena is discussed.