Hadron Multiplicity in Semi-Inclusive Lepton-Nucleon and Lepton-Nucleus Scattering

We discuss multi-hadron production in both inelastic neutrino-nucleon interactions in the current fragmentation region and neutrino-nucleus collisions in the target fragmentation region. Our analysis, carried out within the framework of the quark-gluon string model, is mainly focused on the difference between these two processes. We show that the Q dependence of hadron multiplicity in the current and target fragmentation regions is indeed completely different. The study of inelastic ν − A scattering in the target fragmentation region also provides new information on nuclear structure at small N −N distances. The results of the proposed approach are in satisfactory agreement with the data recently obtained at CERN by the NOMAD Collaboration. PACS. 13.60.Hb Total and inclusive cross sections – 13.15.+g Neutrino interactions