Meson-Nuclear systems are very important and useful objects to extract the meson properties at finite density, which may have the close connections to the symmetry breaking pattern of QCD and its partial restoration in the nucleus. However, the effective densities probed by pionic atoms are known to be around ~ 0.6 rho_0 for almost every pionic state and the change of the chiral order parameter < qbar q > in nuclei is only determined at this specific density. Thus, we are very interested in the density probed by various meson-nuclear systems to know the potentiality of the systems for the studies of the meson properties and the aspects of QCD symmetries at various nuclear densities beyond the linear density approximation.
We consider kaonic systems systematically as a first step. The nuclear density probed by kaonic atoms were studied before and we found that the probed density depended on the states significantly. Thus, the kaonic systems could be more suited to observe various densities than pionic systems. And we performe more systematic studies including both bound and low energy scattering states of K and Kbar mesons.