Inclusive (π, 2π) reactions in nuclei at GeV energies

We discuss the experimental data, in which the emission of secondary mesons produced in different channels of mesons interactions with nuclear targets at several GeV have been studied. In more detail we examine our earlier results concerning the neutral pions emitted in selected channels of peripheral Xe interactions and compare them with the simulation by the modified FRITIOF code. These results show that the problem of mnesonic degrees of freedom of nucleons and nuclei may be investigated in this way. A suggestion is also put forward that the Glauber-Sitenko approach together with the techniques used for the analysis oftk quasi-elastic knockout of pions from nucleons is quite suitable for this purpose