Lattice study of scattering phase shifts for D D * and B B * systems using twisted boundary conditions: Search for bound state formation
Year: 2025
Type: article
Abstract: We investigate the S - and P -wave phase shifts for the D D * and B B * scatterings using Lüscher’s finite-size method under twisted boundary conditions to search for doubly charmed tetraquarks T c c + and doubly bottomed tetraquarks T b b − as the hadronic bound states. The T c c + state was observed as a peak just below the D D * threshold by LHCb Collaboration, while the T b b − state is a theoretically predicted tetraquark state having heavier quark flavors b b u ¯ d ¯ . Lüscher’s finite-size method is one of the well-established methods for calculating the scattering phase shifts between two hadrons in lattice QCD simulations. Several studies have used simulations under the periodic boundary condition to determine the scattering phase shifts at a few discrete momenta for the D D * system. However, the scattering phase shift has not been investigated for the B B * system. In this study, we investigate S - and P -wave scattering phase shifts for the D D * and B B * systems in both I = 0 and I = 1 channels under several types of partially twisted boundary conditions. The use of the partially twisted boundary conditions enables us to obtain the scattering phase shift at any momentum by continuously varying the twisting angle. It also allows us to easily access the P -wave scattering phase shifts through the mixing of S and P waves, which is induced by the imposed boundary conditions. The 2 + 1 flavor PACS-CS gauge ensembles at m π = 295 , 411, and 569 MeV are used. For charm and bottom quarks, the relativistic heavy quark action is adopted to reduce the lattice discretization artifacts due to the heavy quark mass. We discuss the emergence of a shallow bound state with a binding energy of O ( 100 ) keV at the physical pion mass in the B B * system, which has the quantum number
DOI: 10.1103/ksmm-8d7r
Authors: Masato Nagatsuka, Shoichi Sasaki
Institution: Tohoku University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4417267707