2017/04/30 by Neramballi Ripunjay Acharya, Feng-Kun Guo, Ulf-G. Meißner +1
Physics and Astronomy · #Chiral perturbation theory #Effective field theory #Isoscalar #Isovector #Lattice (music) #Lattice QCD #Lattice field theory #Nucleon #Particle physics #Particle physics theoretical and experimental studies #Physics #Physics of Superconductivity and Magnetism #Pion #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum electrodynamics #Quantum mechanics #Scattering #Scattering amplitude #Scattering length #Theoretical physics #hep-lat #hep-ph #nucl-th
paper · pdf · doi:10.1016/j.nuclphysb.2017.07.012
published as Nucl.Phys. B922 (2017) 480-498 · 18 pages, 3 figures, 3 tables
openalex publication_date 2017/07/19 · arxiv created 2017/07/21 · arxiv updated 2017/12/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We show that the interplay of chiral effective field theory and lattice QCD can be used in the evaluation of so-called disconnected diagrams, which appear in the study of the isoscalar and isovector channels of pion–pion scattering and have long been a major challenge for the lattice community. By means of partially-quenched chiral perturbation theory, we distinguish and analyze the effects from different types of contraction diagrams to the pion–pion scattering amplitude, including its scattering lengths and the energy-dependence of its imaginary part. Our results may be used to test the current degree of accuracy of lattice calculation in the handling of disconnected diagrams, as well as to set criteria for the future improvement of relevant lattice computational techniques that may play a critical role in the study of other interesting QCD matrix elements.