Direct CP Violation Asymmetries in Exclusive B Decays in a   Bethe-Salpeter Approach
  CP asymmetry in some exclusive decays of charged B meson are calculated in a Bethe-Salpeter approach. Hadronic final state interactions are ignored. Complex decay amplitudes are assumed to arise entirely from perturbative quark-antiquark loops. Calculations are done both with and without the gluon quark-antiquark vacuum polarization loops. The effects of neglecting the imaginary parts arising from the diagonal quark-antiquark loops are also studied. 
A.N.Kamal and C.W.Luo