Masses of light and heavy mesons in a $U(4)_r \times U(4)_l$ linear   sigma model
  We extend the three-flavor linear sigma model with (axial-)vector mesons to four flavors. We compute the masses of (pseudo)scalar and (axial-)vector mesons including open and hidden charmed mesons as well as weak decay constants. The results are in good agreement with experimental data. 
Walaa I. Eshraim
hep-ph