Proton Profile Function at 52.8 GeV

TL;DR

This paper introduces a model-independent analysis of elastic proton-proton scattering at 52.8 GeV, revealing detailed impact parameter profiles and two distinct dynamical regions within the proton.

Contribution

It provides the first model-independent extraction of the proton profile function at this energy, including uncertainty quantification and insight into its internal structure.

Findings

Real and imaginary parts of the profile show two dynamical regions.

Central dense region extends up to about 1 fm.

Peripheral region spans from 1 to 3 fm.

Abstract

We present the results of a novel model-independent fit to elastic proton-proton differential cross section data at $\sqrt s$ = 52.8 GeV. Taking into account the error propagation from the fit parameters, we determine the scattering amplitude in the impact parameter space (the proton profile function) and its statistical uncertainty region. We show that both the real and imaginary parts of the profile are consistent with two dynamical contributions, one from a central dense region, up to roughly 1 fm and another from a peripheral evanescent region from 1 to 3 fm.