B→Kl+l- with four generations: Rates and CP violation

In the standard model with three generations the branching ratios for BKl+l-+X (BKl+l-) are 1.9×10-6 (0.9×10-6) and 2.4×10-6 (1.2×10-6) for mt=40 and 80 GeV, respectively, with very little uncertainty, and the maximal CP-violation asymmetry is of the order of 1.5%. As demonstrated here in the standard model with four generations, these results may change drastically with a possibility of an increase by more than an order of magnitude in rates and CP-violation asymmetries. The uncertainty is now large for both quantities.