Study on π-A interactions wih outgoing fast protons

The π-A → p1p2...psub(n)+A'+neutrals reaction is studied on C, Al, Cu, Pb nuclei at the π--meson momentum of 3.7 GeV/c. Proton correlations are studied. It is shown that the spectra of protons outgoing backward in the laboratory are similar to the inclusive spectra. The shape of the proton spectrum at laboratory angles exceeding 120 deg weakly depends on the total multiplicity of the protons, on the number of backward protons and on the momentum of fast particles outgoing in the forward direction. There is an evidence that the interaction range is of the order of the nuclear size