On saturation of charged hadron production in pp collisions at LHC

First results on charged hadron transverse momentum spectra in pp collisions obtained by the CMS Collaboration at the LHC are analyzed in the z-scaling approach. These LHC data confirm z-scaling. The saturation regime of the scaling function psi(z) observed in pp and (p) over barp interactions at lower energies root s = 19-1960 GeV is verified. The saturation of psi(z) for charged hadrons is found down to a value of z similar or equal to 0.05 at the highest energy root s = 2360 GeV currently reached by the colliders. A microscopic scenario of hadron production is discussed in connection with the search for new signatures of phase transitions in hadron matter. Constituent energy loss and its dependences on the transverse momentum and collision energy are estimated. We suggest that the beam energy scan program in the saturation region at the LHC could be of interest.