Analysis of unstable particle with the maximum entropy method in O(4) ${\varphi }^4$ theory on the lattice

Abstract

We explore applications of the maximum entropy method (MEM) to determine properties of unstable particles using the four-dimensional O(4) ${\varphi }^4$ theory as a laboratory. The spectral function of the correlation function of the unstable $\sigma$ particle is calculated with MEM, and shown to yield reliable results for both the mass of $\sigma$ and the energy of the two-pion state. Calculations are also made for the case in which $\sigma$ is stable. Distinctive differences in the volume dependence of the $\sigma$ mass and two-pion energy for the stable and unstable cases are analyzed in terms of perturbation theory.

arXiv comment9 pages

References in corpus (4)

• Maximum Entropy Analysis of the Spectral Functions in Lattice QCD
• Spectral function and excited states in lattice QCD with maximum entropy method
• Scattering phases on finite lattices in the broken phase of the four-dimensional O(4)-ϕ^4 theory
• Application of the Maximum Entropy Method to the (2+1)d Four-Fermion Model

Cited by in corpus (6)

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• Spectral Analysis of Excited Nucleons in Lattice QCD with Maximum Entropy Method
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• The mass of the Delta resonance in a finite volume: fourth-order calculation
• Remarks on the Maximum Entropy Method applied to finite temperature lattice QCD