George Rupp

Pion and Kaon Masses and Pion Form Factors from Dynamical Chiral-Symmetry Breaking with Light Constituent Quarks

Light constituent quark masses and the corresponding dynamical quark masses are determined by data, the quark‐level linear σ model, and infrared QCD. This allows to define effective nonstrange and strange current quark masses, which reproduce the experimental pion and kaon masses very accurately, by simple additivity. In contrast, the usual nonstrange and strange current quarks employed by the Particle Data Group and Chiral Perturbation Theory do not allow a straightforward quantitative explanation of the pion and kaon masses.

Explaining the DsJ*(2317)+

The recently observed Ds(2317) meson is explained as a scalar c+anti-s system which appears as a bound state pole, below threshold, in the DK scattering amplitude. The standard c+anti-s charmed scalar D_{s0} is found at about 2.9 GeV, with a width of some 150 MeV. For the scattering length of DK in S wave we predict 5+-1 1/GeV.