Searching For New Physics With B to K pi Decays

We propose a method to quantify the Standard Model uncertainty in B → K π decays using the experimental data, assuming that power counting provides a reasonable estimate of the subleading terms in the 1 / mb expansion. Using this method, we show that present B → K π data are compatible with the Standard Model. We analyze the pattern of subleading terms required to reproduce the B → K π data and argue that anomalously large subleading terms are not needed. Finally, we find that SKS π0 is fairly insensitive to hadronic uncertainties and obtain the Standard Model estimate SKS π0 = 0.74 ± 0.04. © 2009 Elsevier B.V. All rights reserved