B meson decays

Abstract

We discuss the most important Physics thus far extracted from studies of B meson decays. Measurements of the four CP violating angles accessible in B decay are reviewed as well as direct CP violation. A detailed discussion of the measurements of the CKM elements V cb and V ub from semileptonic decays is given, and the differences between resulting values using inclusive decays versus exclusive decays is discussed. Measurements of "rare" decays are also reviewed. We point out where CP violating and rare decays could lead to observations of physics beyond that of the Standard Model in future experiments. If such physics is found by directly observation of new particles, e.g. in LHC experiments, B decays can play a decisive role in interpreting the nature of these particles.

Improved measurements ofDmeson semileptonic decays toπandKmesons

“…Because the magnitudes of CKM matrix elements jV cd j and jV cs j are tightly constrained by CKM unitarity, semileptonic decays of D mesons provide an excellent testing ground for the new theoretical predictions. The relevance of tests using charm decays is increased by the similarity of D meson decays to those of B mesons, where QCD calculations are critical to extractions of jV ub j in exclusive B semileptonic decays [3].…”

Complete(O7,O8)contribution toB¯→X

“…The prediction given in Eq. (1.1) must be compared with the current world averages [13,14], which include measurements from CLEO, BABAR, and Belle [15][16][17]. The central values of the theoretical prediction and of the HFAG average are compatible at the 1:2 level, while both the theoretical and experimental uncertainties are very similar in size (about 7%).…”

The Standard Model of Particle Physics: Status and Low-Energy Tests

“…ε K has been also measured [10,29] through the CP asymmetry between the two K L → π ∓ l ± (−) ν l decay widths, which implies Re (ε K ) = (1.654 ± 0.032) × 10 −3 , in good agreement with (21).…”