Phase-shift calculation using continuum-discretized states

TL;DR

This paper introduces a method for calculating scattering phase shifts using continuum-discretized states, correcting their asymptotic behavior with Green's functions, and demonstrates its effectiveness with nucleon scattering examples.

Contribution

The method provides an accurate way to compute phase shifts from bound-state calculations, improving upon previous approaches by addressing asymptotic behavior issues.

Findings

Accurate phase shifts for $ ext{α}+n$ scattering using realistic potentials.

Discrepancies in $3/2^-$ and $1/2^-$ phase shifts compared to experiment.

Reasonable agreement for $1/2^+$ phase shifts, highlighting tensor and central potential contributions.

Abstract

We present a method for calculating scattering phase shifts which utilizes continuum-discretized states obtained in a bound-state type calculation. The wrong asymptotic behavior of the discretized state is remedied by means of the Green's function formalism. Test examples confirm the accuracy of the method. The $\alpha+n$ scattering is described using realistic nucleon-nucleon potentials. The $3/2^-$ and $1/2^-$ phase shifts obtained in a single-channel calculation are too small in comparison with experiment. The $1/2^+$ phase shifts are in reasonable agreement with experiment, and gain contributions both from the tensor and central components of the nucleon-nucleon potential.