Bound states on the lattice with partially twisted boundary conditions

Understand

We propose a method to study the nature of exotic hadrons by determining the wave function renormalization constant $Z$ from lattice simulations.

• It is shown that, instead of studying the volume-dependence of the spectrum, one may investigate the dependence of the spectrum on the twisting angle, imposing twisted boundary conditions on the fermion fields on the lattice.
• In certain cases, e.g., the case of the $DK$ bound state which is addressed in detail, it is demonstrated that the partial twisting is equivalent to the full twisting up to exponentially small corrections.