Coupled-channel scattering of 𝐷𝐷, 𝐷𝐷*, and 𝐷*𝐷* in isospin-1 from lattice QCD

The first coupled-channel determination of two-body 𝐷 and 𝐷* scattering amplitudes in isospin-1 from lattice quantum chromodynamics (QCD) is presented. Using three lattice volumes at 𝑚𝜋 ≈391 MeV, finite-volume energies relevant for the channels of interest are determined. Through the Lüscher formalism, these energies are used to constrain amplitudes of coupled 𝐽𝑃 =0+ 𝐷⁢𝐷 −𝐷*⁢𝐷*, 𝐽𝑃=1+ 𝐷⁢𝐷*−𝐷*⁢𝐷*, and 𝐽𝑃 =2+ 𝐷⁢𝐷 −𝐷⁢𝐷* −𝐷*⁢𝐷* scattering. All channels feature weakly repulsive interactions in the 𝑆-wave, except for a weak 𝐷*⁢𝐷* attraction in 𝐽𝑃 =0+. No amplitude singularities corresponding to physical states are found. Some of these amplitudes will be a necessary component of future lattice QCD analyses of 𝐷⁢𝐷⁢𝜋 and 𝐷⁢𝐷* scattering, taking into account three-body and left-hand cut effects.