We study infrared contributions to semihard parton-parton interactions by considering an effective charge whose finite infrared behavior is constrained by a dynamical mass scale. Using an eikonal QCD-based model in order to connect this semihard parton-level dynamics to the hadronhadron scattering, we obtain predictions for the proton-proton (pp) and antiproton-proton (pp) total cross sections, σ pp,pp tot , and the ratios of the real to imaginary part of the forward scattering amplitude, ρ pp,pp . We discuss the theoretical aspects of this formalism and consider the phenomenological implications of a class of energy-dependent form factors in the high-energy behavior of the forward amplitude. We introduce integral dispersion relations specially tailored to relate the real and imaginary parts of eikonals with energy-dependent form factors. Our results, obtained using a group of updated sets of parton distribution functions (PDFs), are consistent with the recent data from the TOTEM, AUGER and Telescope Array experiments.

We consider the effect of an energy-dependent dipole form factor in the high-energy behavior of the forward amplitude. The connection between the semihard parton-level dynamics and the hadron-hadron scattering is established by an eikonal QCD-based model. Our results for the proton-proton (pp) and antiproton-proton (pp) total cross sections, σ pp,pp tot (s), obtained using the CTEQ6L1 parton distribution function, are consistent with the recent data from the TOTEM experiment.

At high energies the Pomeron plays a crucial part in describing the soft interactions. In the light of LHC (Large Hadron Collider ) data we perform a detailed analysis of protonproton (pp) and antiproton-proton (pp) forward scattering data in order to determine the intercept and the slope of the soft Pomeron trajectory. This analysis is performed based on Regge theory using Born-level amplitudes. We investigate the role of the protonPomeron vertex form and of the nearest t-channel singularity. We give predictions for the total cross section and the ratio of the real part to the imaginary part of the elastic amplitude in pp collisions at LHC and cosmic-ray energies.