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Total and differential cross-sections have been measured for the reactions $$\pi ^ - p \to (\pi ^0 ,\eta ,\eta \prime )n$$ . The results agree with those of two experiments carried out in the same energy range, apart from measurements at high |t| for the charge-exchange reaction π− p→π0 n. The latter indicate a deviation from the prediction of a single Regge-pole model with linear trajectories at high incident momentum and high momentum transfer.

We present a study of leading protons and antiprotons inp-nucleus and $$\bar p$$ -nucleus on Be, Cu, Ag, W, and U targets. The experiment was performed at the CERN-SPS at a beam energy of 120 GeV. For all targets a suppression of secondary antiprotons with respect to protons is observed. The difference between the $$\bar p$$ andp spectra increases with decreasing χ-values and the effect is stronger for heavier nuclei. The features of the data are qualitatively consistent with multiple-collisions modesls. The data are analysed in terms of a dual parton model which gives a satisfactory description of leadingp and $$\bar p$$ spectra.