2008/04/30 by Guozhan Meng, Chuan Liu · 1 citation
Physics and Astronomy · #Condensed matter physics #Finite volume method #High-Energy Particle Collisions Research #Lattice (music) #Lattice QCD #Particle (ecology) #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #Resonance (particle physics) #Statistical physics #hep-lat
paper · pdf · doi:10.1103/physrevd.78.074506
15 pages, no figures. Title modified. Version to appear on Phys. Rev. D
openalex publication_date 2008/10/09 · arxiv created 2008/10/21 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Volume dependence of the spectral weight is usually used as a simple criteria to distinguish single-particle states from multiparticle states in lattice QCD calculations. Within a solvable model, the Lee model, we show that this criteria is in principle only valid for a stable particle or a narrow resonance. If the resonance being studied is broad, then the volume dependence of the corresponding spectral weight resembles that of a multiparticle state instead of a single-particle one. For an unstable V particle in the Lee model, the transition from single-particle to multiparticle volume dependence is governed by the ratio of its physical width to the typical level spacing in the finite volume. We estimate this ratio for practical lattice QCD simulations and find that, for most cases, the resonance studied in lattice QCD simulations still resembles the single-particle behavior.