2019/04/08 by Antoni J. Woss, Christopher E. Thomas, Jo Dudek +3 · 2 citations
Mathematics · Physics and Astronomy · #Algorithm #Black Holes and Theoretical Physics #Mathematics #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-lat #hep-ph
paper · pdf · doi:10.1103/physrevd.100.054506
published as Phys. Rev. D 100, 054506 (2019)
arxiv created 2019/04/08 · openalex created_date 2019/04/11 · openalex publication_date 2019/09/18 · arxiv updated 2019/09/19 · openalex updated_date 2026/08/06
We present the first lattice QCD calculation of coupled \ensuremathπ\ensuremathω and \ensuremathπ\ensuremathφ scattering, incorporating coupled S and D-wave \ensuremathπ\ensuremathω in JP=1+. Finite-volume spectra in three volumes are determined via a variational analysis of matrices of two-point correlation functions, computed using large bases of operators resembling single-meson, two-meson, and three-meson structures, with the light-quark mass corresponding to a pion mass of m_\ensuremathπ\ensuremath≈391 MeV. Utilizing the relationship between the discrete spectrum of finite-volume energies and infinite-volume scattering amplitudes, we find a narrow axial-vector resonance (JPC=1^+\ensuremath-), the analogue of the b1 meson, with mass mR\ensuremath≈1380 MeV and width \mathrm\ensuremathΓR\ensuremath≈91 MeV. The resonance is found to couple dominantly to S-wave \ensuremathπ\ensuremathω, with a much-suppressed coupling to D-wave \ensuremathπ\ensuremathω, and a negligible coupling to \ensuremathπ\ensuremathφ consistent with the Okubo-Zweig-Iizuka rule. No resonant behavior is observed in \ensuremathπ\ensuremathφ, indicating the absence of a putative low-mass Zs analogue of the Zc seen in \ensuremathπJ/\ensuremathψ. In order to minimally present the contents of a unitary three-channel scattering matrix, we introduce an n-channel generalization of the traditional two-channel Stapp parametrization.