b→s penguin amplitude in charmless B→PP decays -: art. no. 074019

The b -> s penguin amplitude affects a number of B meson decays to two pseudoscalar (P) mesons in which potential anomalies are being watched carefully, though none has yet reached a statistically compelling level. These include (a) a sum of rates for B-0-> K(0)pi(0) and B+-> K(+)pi(0) enhanced relative to half the sum for B-0-> K(+)pi(-) and B+-> K(0)pi(+), (b) a time-dependent CP asymmetry parameter S for B-0-> K(0)pi(0) which is low in comparison with the expected value of sin2 beta similar or equal to 0.73, and (c) a similar deviation in the parameter S for B-0->eta'K-S. These and related phenomena involving vector mesons in the final state are discussed in a unified way in and beyond the standard model. Future experiments which would conclusively indicate the presence of new physics are identified. Several of these involve decays of the strange B meson B-s. In the standard model we prove an approximate sum rule for CP rate differences in B-0-> K(+)pi(-), B+-> K(+)pi(0) and B-0-> K(0)pi(0), predicting a negative sign for the latter asymmetry.