Neutron fragmentation in the reaction pn→pX at 19 GeV/c

Data on the reaction pn→pX are extracted from a pd experiment in the CERN 2m DBC at 19 GeV/c. The cross-section for neutron fragmentation events with |t|<1 (GeV/c)2 is determined and compared with data at high energies at fixedM x 2 /s andt. We find that the cross-section can be described with the triple-Regge formula taking into account only the pion exchange contributions,i.e. the ππP and ππR terms. A leading-particle effect consistent with the pion exchange model is observed in the longitudinal-momentum distribution of the negative pions in the final state of the reaction pn→pX, when transformed to the rest frame of the recoiling system X.