Effects of Final State Interactions on Landau Singularities

TL;DR

This paper investigates how final-state rescattering influences Landau singularities, which can mimic resonance effects, using Landau equations and a modern scattering formalism.

Contribution

It provides a detailed analysis of the impact of final-state interactions on Landau singularities with a novel application of unitarity principles.

Findings

Final-state rescattering can significantly alter Landau singularities.

Landau equations help identify conditions for singularities.

Modern scattering formalism clarifies the role of unitarity in these effects.

Abstract

In certain kinematic and particle mass configurations, triangle singularities may lead to line-shapes which mimic the effects of resonances. This well-known effect is scrutinized here in the presence of final-state rescattering. The goal is achieved first by utilizing general arguments provided by Landau equations, and second by applying a modern scattering formalism with explicit two- and three-body unitarity.