We compute the tree level cross section for gluon-gluon elastic scattering taking into account a dynamical gluon mass, and show that this mass scale is a natural regulator for this subprocess cross section. Using an eikonal approach in order to examine the relationship between this gluon-gluon scattering and the elastic pp andpp channels, we found that the dynamical gluon mass is of the same order of magnitude as the ad hoc infrared mass scale m 0 underlying eikonalized QCD-inspired models. We argue that this correspondence is not an accidental result, and that this dynamical scale indeed represents the onset of nonperturbative contributions to the elastic hadron-hadron scattering. We apply the eikonal model with a dynamical infrared mass scale to obtain predictions for σ pp,pp tot , ρ pp,pp , slope B pp,pp , and differential elastic scattering cross section dσp p /dt at Tevatron and CERN-LHC energies.

We describe the formalism, and present the results, for a triple-Regge analysis of the available pp and pp high-energy data which explicitly accounts for absorptive corrections. In particular, we allow for the gap survival probability, S 2 , in single proton diffractive dissociation. Since for pp scattering the value of S 2 is rather small, the triple-Pomeron vertex obtained in this analysis is larger than that obtained in the old analyses where the suppression caused by the absorptive corrections was implicitly included in an effective vertex. We show that the bare triple-Pomeron coupling that we extract from the pp and pp data is consistent with that obtained in a description of the γp → J/ψ + Y HERA data. The analyses of the data prefer a zero slope, corresponding to the small size of the bare vertex, giving the hope of a smooth matching to the perturbative QCD treatment of the triple-Pomeron coupling.

Analytic models for hadron-hadron scattering are characterized by simple analytical parametrizations for the forward amplitudes and the use of dispersion relation techniques to study the total cross section σtot and the ρ parameter (the ratio between the real and imaginary parts of the forward amplitude). In this paper we investigate simultaneously four aspects related to the application of the model to pp andpp scattering, from accelerator to cosmic-ray energies: (1) the effect of different estimations for σtot from cosmic-ray experiments; (2) the differences between individual and global (simultaneous) fits to σtot and ρ; (3) the role of the subtraction constant in the dispersion relations; (4) the effect of distinct asymptotic inputs from different analytic models. This is done by using as a framework the single Pomeron and the maximal Odderon parametrizations for the total cross section. Our main conclusions are the following: (1) Despite the small influence from different cosmic-ray estimations, the results allow us to extract an upper bound for the soft Pomeron intercept: 1 + ǫ = 1.094; (2) although global fits present good statistical results, in general, this procedure constraints the rise of σtot; (3) the subtraction constant as a free parameter affects the fit results at both low and high energies; (4) independently of the cosmic-ray information used and the subtraction constant, global fits with the Odderon parametrization predict that, above √ s ≈ 70GeV, ρpp(s) becomes greater than ρpp(s), and this result is in complete agreement with all the data presently available. In particular, we infer ρpp = 0.134 ± 0.005 at √ s = 200 GeV and 0.151 ± 0.007 at 500 GeV (BNL RHIC energies). A detailed discussion of the procedures used and all the results obtained is also presented.

By using an extended Regge parametrization and taking into account the discrepancies in the high-energy pp and p(bar)p total cross section data, in both accelerator and cosmic-ray regions, we estimate extrema bounds for the soft Pomeron intercept. First we consider two ensembles of data with either the CDF or the E710 and E811 results for the p(bar)p total cross section at 1.8 TeV, from which we obtain the bounds 1.102 and 1.081, respectively. These ensembles are then combined with the highest and lowest estimations for the pp total cross section from cosmic-ray experiments (6-40 TeV), leading to the upper and lower bounds 1.109 and 1.082, respectively. The effects of simultaneous fits to total cross sections and the rho parameter, individual fits to total cross sections, and the influence of the subtraction constant in the dispersion relations are also presented. Our global results favor the E710 and E811 data.Comment: 7 pages, 7 figures, aps-revtex, to be published in Physics Letters