2016/10/10 by Meng-Lin Du, Feng-Kun Guo, Ulf-G. Meißner +1 · 2 citations
Physics and Astronomy · #Boson #Chiral perturbation theory #Chiral symmetry breaking #Coupling constant #Goldstone boson #High-Energy Particle Collisions Research #Lattice QCD #Meson #Particle physics #Particle physics theoretical and experimental studies #Physics #Pseudoscalar #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Unitarity #hep-ph
paper · pdf · doi:10.1103/physrevd.94.094037
published as Phys. Rev. D 94, 094037 (2016) · 26 pages, 5 figures, 4 tables
arxiv created 2016/10/10 · openalex publication_date 2016/11/28 · arxiv updated 2016/12/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the numerical values of the low-energy constants in the chiral effective Lagrangian for the interactions between the charmed mesons and the lightest pseudoscalar mesons, the Goldstone bosons of the spontaneous breaking of chiral symmetry for QCD. This problem is tackled from two sides: estimates using the resonance-exchange model and positivity constraints from the general properties of the S-matrix including analyticity, crossing symmetry, and unitarity. These estimates and constraints are compared with the values determined from fits to lattice data of the scattering lengths. Tensions are found, and possible reasons are discussed. We conclude that more data from lattice calculations and experiments are necessary to fix these constants better. As a byproduct, we also estimate the coupling constant g_DDa2, with a2 the light tensor meson, via the QCD sum rule approach.