Relativistic multirank interaction kernels of the neutron-proton system

TL;DR

This paper develops relativistic multirank interaction kernels for neutron-proton scattering, accurately modeling phase shifts up to 3 GeV and comparing favorably with existing models.

Contribution

It introduces two methods for relativistically generalizing nonrelativistic form factors in neutron-proton interaction kernels, enhancing modeling accuracy.

Findings

Successfully describes experimental phase shifts up to 3 GeV

Provides a comparison with other neutron-proton interaction models

Offers a new relativistic approach to multirank kernels

Abstract

The multirank separable kernels of the neutron-proton interaction for uncoupled $S$ and $P$ partial waves (with the total angular momentum $J$=0,1) are proposed. Two different methods of a relativistic generalization of initially nonrelativistic form factors parametrizing the kernel are considered. Using the constructed kernels the experimental data for phase shifts in the elastic neutron-proton scattering for the laboratory energy up to 3 GeV and low-energy parameters are described. The comparison of our results with other model calculations are presented.