Do we really understand nuclear reactions within thick targets using GeV-hadrons?

Three experimental evidences are presented to show that, using classical concepts of physics, we are unable to understand the interaction of 72 GeV 40Ar (and 44 GeV 12C) and their relativistic secondary fragments in thick Cu-targets. The first observation is connected with fragmentation products of mass A in the range of 10≤A≤40, in particular to the production of more-than-calculated yields of 24Na. The reason for this unexpected behavior is due to some enhanced interaction properties for relativistic secondary fragments. Moreover, due to the observation of constant classical total interaction cross sections for primary and secondary hadrons, this enforces a reduced production of spallation products being close to the target, as is in fact experimentally observed (the second evidence). The third experimental observation is a more-than-linear increase in the production of secondary neutrons for reactions induced by 44 GeV 12C in thick Pb- and Cu-targets as compared to 12 GeV 12C. This can be understood within the context of the first two experimental evidences. These effects are experimentally confirmed above about 40 GeV for hadronic primaries, however, they may even extend down to 1 GeV primary hadron energy. Results are discussed within the context of a new theoretical approach