Tracing masses of ground-state light-quark mesons
  We describe a symmetry-preserving calculation of the meson spectrum, which combines a description of pion properties with reasonable estimates of the masses of heavier light-quark mesons, including axial-vector states. The kernels used in formulating the problem are essentially nonperturbative. They incorporate effects of dynamical chiral symmetry breaking (DCSB) that were not previously possible to express. Our analysis clarifies a causal connection between DCSB and the splitting between vector and axial-vector mesons, and exposes a key role played by the anomalous chromomagnetic moment of dressed-quarks in forming the spectrum. 
Lei Chang and Craig D. Roberts
nucl-th hep-lat hep-ph nucl-ex