Charge Splitting in πNΔ Form Factor

Abstract

Experimental data on πN scattering in the elastic energy region w ≤ 1.45 GeV are analyzed within the K-matrix approach with effective lagrangians. The charge splitting in δ₃₃⁺⁺ and δ₃₃⁰ phases obtained 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 form factors of the Δ⁺⁺ and Δ⁰ only. This means that πNΔ⁺⁺ and πNΔ⁰ interactions have a different range. The underlying nature of the observed phenomena is discussed.