FUSION OF STRINGS - CONSEQUENCES AT THE HIGHEST COSMIC-RAY ENERGIES

Possible consequences at the highest cosmic ray energies of the collec tive effects, invoked to explain some features of heavy ion data at AG S and SPS (10-20 GeV per nucleon in center of mass system) are discuss ed. The fusion of the strings produced in the collision, have been int roduced in the usual models of soft hadronic and nuclear interactions like DPM/QGSM to explain the strangeness enhancement, found in heavy i on collisions. Two effects of string fusion, namely the reduction of m ultiplicities and the enhancement of cumulative production, should str ongly affect the first interactions in the shower and could be of impo rtance to explain two features of the highest energy cosmic rays: thei r composition and the energy of the primary.