On the isospin properties of the weak neutral current

Abstract The Gargamelle results on the one pion neutral current reactions ν (or ν )+ N →ν(or ν )+N+π have been analyzed in order to deduce the isospin properties of the neutral current reactions. The results of this analysis are in disagreement with the hypothesis of a pure ΔI =0 transition, and are compatible with at least an important contribution from a ΔI =1 transition.