Partial Wave Analysis of Nucleon-Nucleon Scattering below pion production threshold

TL;DR

This paper performs a detailed partial wave analysis of proton-proton and neutron-proton scattering data below pion production threshold, modeling interactions with delta-shells and one pion exchange, achieving a good fit and estimating uncertainties.

Contribution

It introduces a combined delta-shell and one pion exchange model for nucleon-nucleon interactions below 350MeV with comprehensive error analysis.

Findings

Achieved chi^2/d.o.f = 1.06 indicating a good fit.

Provided detailed error estimates for phase-shifts and scattering amplitudes.

Successfully modeled nucleon-nucleon interactions with a minimal set of parameters.

Abstract

We undertake a simultaneous partial wave analysis to proton-proton and neutron-proton scattering data below pion production threshold up to LAB energies of 350MeV. We represent the interaction as a sum of delta-shells in configuration space below 3fm and a charge dependent one pion exchange potential above 3fm together with electromagnetic effects. We obtain chi^2 = 2813|pp + 3985|np with a total of N = 2747|pp + 3691|np data obtained till 2013 and a total number of 46 fitting parameters yielding chi^2 /d.o.f = 1.06. Special attention is paid to estimate the errors of the phenomenological interaction as well as the derived effects on the phase-shifts and scattering amplitudes.