Resonance Scattering Phase Shifts in a 2-d Lattice Model

TL;DR

This paper investigates resonance scattering phase shifts in a 2D lattice model with two coupled fields, using Monte Carlo simulations to extract physical parameters like resonance mass and width.

Contribution

It introduces a method to determine phase shifts and resonance parameters from lattice simulations of a simple 2D coupled-field model.

Findings

Resonance mass and width are successfully extracted from lattice data.

The phase shift behavior confirms the resonance nature of the scattering.

The representation of scattering states in the lattice model is analyzed.

Abstract

We study a simple 2-d model representing two fields with different mass and a 3-point coupling term. The phase shift in the resonating 2-particle channel is determined from the energy spectrum obtained in Monte Carlo simulations on finite lattices. Masses and wave function renormalization constants of the fields as well as mass and width of the resonance are determined and discussed. The representation of scattering states in terms of the considered operators is analysed.