Quark and gluon dynamics from heavy meson spectroscopy

The M1 decay rates of heavy quarkonia and the pionic decay rates of heavy-light mesons are sensitive to the form of both the confining and the hyperfine interactions between quarks. The present data on these decay rates rule out vector coupled confinement. The pionic decay rates of the excited D-mesons determine the coupling between pions and light constituent quarks. The unifying feature of these decays is the suppression of the spin current and axial charge operator caused by the confining interaction.