More Precise Determination of V_{cb} & V_{ub} and Direct CP Violation in Charmless B Decays

Abstract

More precise extractions on the two important CKM matrix elements $|V_{cb}|$ and $|V_{ub}|$ are presented up to $1/m_Q^2$ corrections based on the complete heavy quark effective field theory (HQEFT) of QCD. The HQEFT as a large component QCD provides us a complete theoretical framework for correctly and systematically evaluating the subleading and higher order contributions in $1/m_Q$ expansion of heavy quarks. A global analysis on charmless B decays is made based on the isospin and SU(3) flavor symmetry. An isospin relation is found to be very useful for studying SU(3) symmetry breaking effects of strong phases and exploring new type of electroweak penguin effects. The direct CP violation in charmless B decays is predicted and its precise measurement is helpful either for testing SU(3) symmetry breaking effects of strong phases or for probing new physics beyond standard model.