A Critical Study of the B -> K \pi Puzzle
  In the light of new experimental results on B -> K pi decays, we critically study the decay processes B -> K pi in a phenomenological way. Using the quark diagram approach and the currently available data, we determine the allowed values of the relevant theoretical parameters, corresponding to the electroweak (EW) penguin, the color-suppressed tree contribution, etc. In order to find the most likely values of the parameters in a statistically reliable way, we use the chi^2 minimization technique. Our result shows that the current data for B to K pi decays strongly indicate (large) enhancements of both the EW penguin and the color-suppressed tree contributions. In particular, the color-suppressed tree effect needs to be enhanced by about an order of magnitude to fit the present data. 
C.S. Kim, Sechul Oh, Chaehyun Yu