Abstract
We use the one-loop chiral perturbation theory -scattering amplitude and dispersion theory in the form of the inverse amplitude method to study the quark-mass dependence of the two lightest resonances of the strong interactions, the () and the meson. As the main results, we find that the coupling constant is almost quark mass independent and that the mass shows a smooth quark-mass dependence while that of the shows a strong nonanalyticity. These findings are important for studies of the meson spectrum on the lattice.
- Received 18 January 2008
DOI:https://doi.org/10.1103/PhysRevLett.100.152001
©2008 American Physical Society