Strong longitudinal color-field effects in pp collisions at energies available at the CERN Large Hadron Collider

We study the effect of strong longitudinal color fields (SCF) in p + p reactions up to Large Hadron Collider (LHC) energies in the framework of the HIJING/B (B) over bar (v2.0) model that combines (collinear factorized) perturbative quantum chromodynamics multiple minijet production with soft longitudinal string excitation and hadronization. The default vacuum string tension kappa(0) = 1 GeV/fm, is replaced by an effective energy-dependent string tension kappa(s) =kappa(0)(s/s(0))(0.06) that increases monotonically with center-of-mass energy. The exponent lambda = 0.06 is found sufficient to reproduce well the energy dependence of multiparticle observables in the Relativistic Heavy Ion Collider, Tevatron, as well as recent LHC data. This exponent is half of that predicted by the color glass saturation (CGC) model, lambda(CGC) = 0.115, where gluon fusion multiparticle production mechanisms are assumed. In HIJING/B (B) over bar (v2.0), the rapid growth of dN(ch)/d eta with energy is due to the interplay of copious minijet production with increasing SCF contributions. The large (strange) baryon-to-meson ratios measured at Tevatron energies are well described. A significant enhancement of these ratios is predicted up to the highest LHC energy (14 TeV). The effect of JJ loops and SCF on baryon-antibaryon asymmetry, and its relation to baryon number transport, is also discussed.