The reaction pi+ p --> K+ Sigma+ in a unitary coupled-channels model

TL;DR

This paper develops a unitary coupled-channels model to describe pi N scattering and the pi+ p --> K+ Sigma+ reaction, incorporating analyticity and SU(3) symmetry, and compares results with experimental data.

Contribution

It introduces a novel unified approach that simultaneously models elastic scattering and reaction channels with a focus on analyticity and flavor symmetry.

Findings

Successfully describes angular distributions, polarizations, and spin-rotation parameters.

Extracts pole structures of amplitudes through analytic continuation.

Provides insights into meson-baryon interactions and resonance properties.

Abstract

Elastic pi N scattering and the reaction pi+ p --> K+ Sigma+ are described simultaneously in a unitary coupled-channels approach which respects analyticity. SU(3) flavor symmetry is used to relate the t- and u-channel exchanges that drive the meson-baryon interaction in the different channels. Angular distributions, polarizations, and spin-rotation parameters are compared with available experimental data. The pole structure of the amplitudes is extracted from the analytic continuation.