B Decays


Book Description

This 2nd edition is an extensive update of "B Decays?. The revisions are necessary because of the extensive amount of new data and new theoretical ideas. This book reviews what is known about b-quark decays and also looks at what can be learned in the future.The importance of this research area is increasing, as evidenced by the approval of the luminosity upgrade for CESR and the asymmetric B factories at SLAC and KEK, and the possibility of experiments at hadron colliders.The key experimental observations made thus far, measurement of the lifetimes of the different B species, B0-B0 mixing, the discovery of ?Penguin? mediated decays, and the extraction of the CKM matrix elements Vub and Vcb from semileptonic decays, as well as more mundane results, are described in great detail by the experimentalists who have been closely involved with making the measurements. Theoretical progress in understanding b-quark decays using HQET and lattice gauge techniques are described by theorists who have developed and used these techniques.Synthesizing the experimental and theoretical information, several articles discuss the implications for the ?Standard Model? and how further tests can be done using measurements of CP violation in the B system.




Investigation of Semileptonic B Meson Decay to P-Wave Charm Mesons


Book Description

We have studied semileptonic B meson decays with a P-wave charm meson in the final state using 3.29 x 10[sup 6] B[bar B] events collected by the CLEO II detector at the Cornell Electron-positron Storage Ring. We find a value for the exclusive semileptonic product branching fraction:[Beta](B[sup -][yields] D[sub 1][sup 0][ell][sup -][bar[nu]][sub[ell]])[Beta](D[sub 1][sup 0][yields] D*[sup+][pi][sup -])= (0.373[+-] 0.085[+-] 0.052[+-] 0.024)% and an upper limit for[Beta](B[sup -][yields] D*[sub 2][sup 0][ell][sup -][bar[nu]][sub[ell]])[Beta](D*[sub 2][sup 0][yields] D*[sup+][pi][sup -])










Soft Pion Emission in Semileptonic B-meson Decays


Book Description

An analysis of semileptonic decays of B mesons with the emission of a single soft pion is presented in the framework of the heavy-quark limit using an effective Lagrangian which implements chiral and heavy-quark symmetries. The analysis is performed at leading order of the chiral and inverse heavy mass expansions. In addition to the ground state heavy mesons some of their resonances are included. The estimates of the various coupling constants and form factors needed in the analysis are obtained using a chiral quark model. As the main result, a clear indication is found that the 0 and 1+ resonances substantially affect the decay mode with a D{sup *} in the final state, and a less dramatic effect is also noticed in the D mode. An analysis of the decay spectrum in the D{sup *}-?2 invariant mass is carried out, showing the main effects of including the resonances. The obtained rates show promising prospects for studies of soft pion emission in semileptonic B-meson decays in a B-meson factory where, module experimental cuts, about 105 such decays in the D meson mode and 104 in the D{sup *} mode could be observed per year.