Partially conserved axial-vector current conditions on strange-particle photoproduction and electroproduction amplitudes

Abstract

The photoproduction and electroproduction of strange particles on nucleons are studied in the framework of the algebra of currents and the partially conserved axial-vector current. Consistency conditions are derived for the non-Born amplitudes\(\bar A_1^{( \pm ,0)} (0),\bar A_6^{( \pm ,0)} (0)\), in the process γ +N → Σ + K and for the amplitudes\(\bar A_1^{(S,V)} (0),\bar A_6^{(S,V)} (0)\), in the reaction γ +N → Λ + K. Evaluating these amplitudes using low-lying baryon resonant states we calculate the magnetic moments of the Λ, Σ− and Σ0 as well as the Dirac and axial-vector current mean square radii of the baryons. The Λ magnetic moment agrees with the available experimental value. The Dirac mean square radii are found to be in good agreement with theSU3 predictions. The value derived for the β-decay axial-vector mean square radius is found to be consistent with the value obtained from pion electroproduction.