2013/01/22 by Oliver Bär, Oliver Bar, Maarten Golterman +2
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-lat
paper · pdf · doi:10.48550/arxiv.1301.5151
6 pages, contribution to Chiral Dynamics 2012
arxiv created 2013/01/22 · arxiv updated 2013/01/23
We study multi-particle state contributions to the QCD two-point functions of pseudo-scalar quark bilinears in a finite spatial volume. For sufficiently small quark masses one expects three-meson states with two additional pions at rest to have the lowest total energy after the ground state. Using chiral perturbation theory, we find the amplitude of this state to be too small to be seen in present-day lattice simulations. We speculate that curvature in the effective mass plot extracted from the pseudo-scalar density two-point function instead corresponds to a genuine resonance, the π(1300).