A vertex-structure model for new direct CP-violating effects in   Bbar^0(B^0) -> phi K_S and in B^-+ -> pi^-+ eta' (eta)
  We consider effective Lagrangian models of CP-violating vertex structure in which a $b -> uW$ vertex, proportional to $s_{13}e^{-i\delta_{13}}$ with $s_{13}$ very small (milliweak interaction) and $\delta_{13}$ large, is dynamically generated. A consequent, enhanced CP-violating vertex for $b\to sg$ results in an enhanced CP-violating phase in the ratio of amplitudes for $\bbar \to \phi \KS$. We estimate that this can significantly change the $S$ parameter from the value expected in the standard model. 
Saul Barshay and Georg Kreyerhoff