Consequences of parton's saturation and string's percolation on the   developments of cosmic ray showers
  At high gluon or string densities, gluons' saturation or the strong interaction among strings, either forming colour ropes or giving rise to string's percolation, induces a strong suppression in the particle multiplicities produced at high energy. This suppression implies important modifications on cosmic ray shower development. In particular, it is shown that it affects the depth of maximum, the elongation rate, and the behaviour of the number of muons at energies around 10^{17}-10^{18} eV. The existing cosmic ray data point out in the same direction. 
C. Pajares, D. Sousa, and R.A. V\'azquez (Departamento de F\'isica de   Part\'iculas, Universidade de Santiago, Spain)