Analytic Amplitude Models for Forward Scattering

TL;DR

This paper evaluates various analytic amplitude models for forward scattering using extensive data, introducing new quantitative indicators to assess fit quality, and finds that models with a universal log^2 s Pomeron term perform best, extending to lower energies.

Contribution

It introduces novel quantitative indicators for assessing the goodness of fit of amplitude models and demonstrates the superiority of models with a universal log^2 s Pomeron term.

Findings

Universal log^2 s Pomeron term models fit data well

Indicators improve fit quality assessment

Models extend to energies as low as 4 GeV

Abstract

We report on fits of a large class of analytic amplitude models for forward scattering against the comprehensive data for all available reactions. To differentiate the goodness of the fits of many possible parametrizations to a large sample of data, we developed and used a set of quantitative indicators measuring statistical quality of the fits over and beyond the typical criterion of the $\Chi^2 /dof$. These indicators favor models with a universal $ log^2 s$ Pomeron term, which enables one to extend the fit down to $\sqrt s = 4$ GeV.