Our past research has developed techniques and programs to solve for bound and scattering states simultaneously. In particular, we have investigated interactions in momentum space with both short range (nuclear) parts and long range (Coulomb) parts. Further developments have extended the work to coupled channels and to many-nucleon systems. Systems studied include (K-p, Sigma pi, Lambda pi), (pi N, pi Delta), (Nbar N, X), K- C, and pi Pb. While making these calculations, we strive to use as good an elementary interaction model as is available, and often develop them ourselves for this purpose. For example, we performed the first simultaneous calculations of bound and scattering states in the chiral color dielectric and bag quark models, as well as searched for deep, Coulomb assisted nuclear bound states of mesons within nuclei with a nonlocal nuclear potential. Our work on kaonic hydrogen has been particularly extensive, with recent experiments finding agreement with our former predictions.
We propose to continue these types of investigations in which the hadron interactions are modeled dynamically and the interactions are either placed within a nucleus, or combined with the Coulomb force to form an exotic atom. These are stringent (off-shell) tests of the interactions being developed.
In the absence of any strong interaction, the D- meson will form atomic states bound. When the strong interaction is represented by the quark-meson coupling (QMC) model, our collaboration with University of Adelaide has recently shown that the D- will form narrow bound states with Pb. The possibility of D- bound states is exciting. It provides information on the nature of the interaction between charmed mesons and nuclear matter, and, specifically, on the relativistic mean fields in nuclei and the nature of dynamical symmetry breaking.
We calculated the mean field potentials for the D0, D-bar-0 and D- mesons in Pb self-consistently using the QMC model in local density approximation. The meson-Pb bound state energies were calculated using the momentum-space techniques and codes developed by Oregon State. We found that the resulting binding for the 1s level in Pb is between 10 and 30 MeV and should provide a very clear experimental signature. We also concluded that sheer knowledge of whether or not a D-bar-0 Pb bound state exists would give new information as to whether the interactions of light quarks in a heavy meson are the same as those in a nucleon.