High-Energy Forward Scattering and the Pomeron: Simple Pole versus Unitarized Models

TL;DR

This paper analyzes extensive scattering data to compare simple-pole and unitarized models of the pomeron, concluding current data cannot distinguish their fundamental nature but supports the simple-pole hypothesis.

Contribution

It provides a comprehensive comparison of models using the largest available data set and evaluates the validity and implications of each approach in high-energy scattering.

Findings

Data cannot discriminate between simple-pole and log-squared fits.

Evidence favors the simple-pole hypothesis based on factorization and universality.

Fits are unreliable below 9 GeV energy.

Abstract

Using the largest data set available, we determine the best values that the data at t=0 (total cross sections and real parts of the hadronic amplitudes) give for the intercepts and couplings of the soft pomeron and of the rho/omega and a/f trajectories. We show that these data cannot discriminate between a simple-pole fit and asymptotic log square s and log s fits, and hence are not sufficient to reveal the ultimate nature of the pomeron. However, we evaluate the existing evidence (factorization, universality, quark counting) favouring the simple-pole hypothesis. We also examine the range of validity in energy of the fits, and show that one cannot rely on such fits in the region sqrt(s)<9 GeV. We also establish bounds on the odderon and the hard pomeron.