Meson structure in a relativistic many-body approach

Results from an extensive relativistic many-body analysis utilizing a reali stic effective QCD Hamiltonian are presented for the meson spectrum. A comp arative numerical study of the BCS, Tamm-Dancoff (TDA), and RPA treatments provides new, significant insight into the condensate structure of the vacu um, the chiral symmetry governance of the pion, and the meson spin, orbital , and flavor mass splitting contributions. In contrast to a previous glueba ll application, substantial quantitative differences are computed between T DA and RPA for the light quark sector with the pion emerging as a Goldstone boson only in the RPA.