Energy-dependent partial-wave analysis of all antiproton-proton scattering data below 925 MeV/c

TL;DR

This paper performs an energy-dependent partial-wave analysis of antiproton-proton scattering data below 925 MeV/c, incorporating long-range chiral interactions and parametrizing short-range effects, resulting in a comprehensive phase-shift analysis.

Contribution

It introduces a new analysis method that includes exact long-range chiral interactions and a complex boundary condition for short-range effects, improving the understanding of antiproton-proton scattering.

Findings

Achieved a good fit with chi^2_min/N_df=1.048

Provided detailed phase-shift parameters for antiproton-proton scattering

Included significantly more high-quality charge-exchange data

Abstract

We present a new energy-dependent partial-wave analysis of all antiproton-proton elastic and charge-exchange scattering data below 925 MeV/c antiproton laboratory momentum. The long-range parts of the chiral one- and two-pion exchange interactions are included exactly. The short-range interactions, including the coupling to the mesonic annihilation channels, are parametrized by a complex boundary condition at a radius of r=1.2 fm. The updated database, which includes significantly more high-quality charge-exchange data, contains 3749 scattering data. The fit results in chi^2_min/N_df=1.048, where N_df=3578 is the number of degrees of freedom. We discuss the description of the experimental data and we present the antiproton-proton phase-shift parameters.