Role of resonances in production of cumulative π mesons on nuclei

It is shown that the high-energy part of the inclusive spectrum of cumulative pions produced in the reactions NA..--> pi..X at large initial energies is dominated by processes involving production of boson resonances in the intermediate state. These processes must be taken into account, especially at energies for which pion production in NN interactions proceeds mainly via vector mesons. The A-dependence of the spectra is considered in a model of multiple scattering. The theory is compared with experiment at E/sub 0/ = 400 GeV.