Lattice QCD analysis of the H-dibaryon including left-hand-cut effects
Understanding exotic matter, composed of states that go beyond the conventional quark-antiquark and three-quark pictures, is a central goal of modern hadron physics. Lattice QCD offers a first-principles path to study these systems through finite-volume spectra, which can be related to scattering amplitudes. For several exotic candidates, long-range exchange mechanisms produce left-hand-cut branch points in the amplitudes close to the relevant energy region, requiring methods that incorporate these effects explicitly.
This work, carried out by Arkaitz Rodas (ODU & JLab, co-PI), Lin Qiu (ODU & JLab), Cesar Fernandez-Ramirez (UNED), Vincent Mathieu (Barcelona U., co-PI), Gloria Montana (Barcelona U.), Alessandro Pilloni (Messina U. & INFN Catania, co-PI), and Adam Szczepaniak (Indiana U. & JLab, PI), presents the first application of the finite-volume $N/D$ formalism with explicit left-hand-cut effects to lattice-QCD two-body spectra. The method is applied to the flavor-singlet two-baryon channel associated with the $H$-dibaryon hexaquark candidate, using lattice data at the $SU(3)_F$-symmetric point.
The analysis compares the $N/D$ description, including one-pion exchange, with conventional Lüscher fits based on effective-range expansions. While all approaches support a shallow bound $H$-dibaryon near threshold, the $N/D$ result shows that left-hand cuts lead to statistically meaningful shifts in the extracted pole observables for this state.
This work, carried out by Arkaitz Rodas (ODU & JLab, co-PI), Lin Qiu (ODU & JLab), Cesar Fernandez-Ramirez (UNED), Vincent Mathieu (Barcelona U., co-PI), Gloria Montana (Barcelona U.), Alessandro Pilloni (Messina U. & INFN Catania, co-PI), and Adam Szczepaniak (Indiana U. & JLab, PI), presents the first application of the finite-volume $N/D$ formalism with explicit left-hand-cut effects to lattice-QCD two-body spectra. The method is applied to the flavor-singlet two-baryon channel associated with the $H$-dibaryon hexaquark candidate, using lattice data at the $SU(3)_F$-symmetric point.
The analysis compares the $N/D$ description, including one-pion exchange, with conventional Lüscher fits based on effective-range expansions. While all approaches support a shallow bound $H$-dibaryon near threshold, the $N/D$ result shows that left-hand cuts lead to statistically meaningful shifts in the extracted pole observables for this state.
Papers: arXiv:2605.22957