CP violation in the decays of neutral B-mesons

Summary

Theoretical predictions are given for the branching ratios and theCP violating time-integrated asymmetries for the decays into two pseudoscalar mesons of the pseudoscalar neutral particles with definite beauty att=0 and strangenessS=0, ±1. For some of the considered decays these asymmetries depend only, or mainly, on the values of the elements of the Kobayashi-Maskawa matrix; the present knowledge about them, in particular the uncertainty on the value of theCP-violating phase δ, affects the precission of the predictions. As long as the decays of B ⁰_d and$\bar B_d^0$ into final states with predicted branching ratios larger than 10⁻⁴ are concerned, positive asymmetries are expected for$\Upsilon _{1C} K_1^0$ K ⁰₁ (in the range from 10% to 37%) and D⁺D⁻ (12% to 39%) and a small negative asymmetry for$D\pi ^ +$ (−0.3% to −2%). The asymmetry for$\pi ^ + \pi ^ -$ (from −32% to 47%) shows a strong dependence on the explicit evaluation of the weak amplitude and on the sign of cos δ. Smaller asymmetries are predicted for the decays of B ⁰_s and$\bar B_S^0$ as a consequence of the large value expected for the mixing parameters$z_S = \Delta M_S /\Gamma _S$. A negligible effect is found for F⁺F⁻ (from −0.1% to −0.5%), whereas a larger one occurs for F^±K^∓ (from 1% to 8%) and$F^ \pm K^ \mp$ (from −3% to −6%).