Fourth Generation CP Violation Effect on B -> K pi, phi K and rho K in   NLO PQCD
  We study the effect from a sequential fourth generation quark on penguin-dominated two-body nonleptonic B meson decays in the next-to-leading order perturbative QCD formalism. With an enhancement of the color-suppressed tree amplitude and possibility of a new CP phase in the electroweak penguin, we can account better for A_{CP}(B^0 -> K^+ pi^-)-A_{CP}(B^+ -> K^+ pi^0). Taking |V_{t's}V_{t'b}| \sim 0.02 with phase just below 90^\circ, which are consistent with the b -> s l^+ l^- rate and the B_s mixing parameter \Delta m_{B_s}, we find a downward shift in the mixing-induced CP asymmetries of B^0 -> K_S pi^0 and phi K_S. The predicted behavior for B^0 -> rho^0 K_S is opposite. 
Wei-Shu Hou, Hsiang-nan Li, Satoshi Mishima, Makiko Nagashima