The penguin mediated processes b → sg and b → sl+l− are studied. In the Standard Model, for the leptonic modes improvement in experimental limits will put strigient bounds on the top mass, where the present limit from b → sμ+μ− is 390 GeV. For hadronic penguin processes, although the gluonic penguin dominates, we find the electroweak contribution are around 30% for the upper range allowed top m...

The talk summarises a calculation of the two-point functions for ∆S = 1 current-current and QCD-penguin operators, as well as for the ∆S = 2 operator, at the next-to-leading order. The size of the gluonic corrections to current-current operators is large, providing a qualitative understanding of the observed enhancement in ∆I = 1/2 transitions. In the ∆S = 2 sector the QCD corrections are quite...

The role of B decays in the study of CP violation is reviewed. We treat the interactions and spectroscopy of the b quark and then introduce CP violation in B meson decays, including time-dependences, decays to CP eigenstates and non-eigenstates, and flavor tagging. Additional topics include studies of strange B’s, decays to pairs of light pseudoscalar mesons, and the roles of gluonic and electr...

We review the recent results on the measurement of |Vcb| and charmless hadronic B decays from CLEO based on 9.7×10 BB pairs collected with CLEO II and II.V detectors. The preliminary result on the measurement of |Vcb| is |Vcb| = (46.4 ± 2.0 ± 2.1 ± 2.1) × 10 . The comprehensive measurement on exclusive charmless hadronic B decays indicate existence of many contributing and interfering diagrams,...

I discuss the comparison of the current theoretical calculations of ε/ε with the experimental data. Lacking reliable “first principle” calculations, phenomenological approaches may help in understanding correlations among different contributions and available experimental data. In particular, in the chiral quark model approach the same dynamics which underlies the ∆I = 1/2 selection rule in kao...

Using 3.3 Million BB̄ pairs accumulated with the CLEO detector we have measured B(B → Kπ) = (1.5 −0.4 ± 0.1± 0.1)× 10, B(B → Kπ) = (2.3 −1.0 ± 0.2± 0.2)× 10, and B(B → η′K+) = (7.8 −2.2±1.0)×10. These constitute the first observations of exclusive B decays to charmless hadronic final states. Furthermore, a measurement of B(B → hπ) = (1.6 +0.3 −0.5 −0.2 ± 0.1) × 10, as well as upper limits on var...

The 2–point functions for ∆S = 1 current-current and QCD-penguin operators, as well as for the ∆S = 2 operator, are calculated at the next-to-leading order. The calculation is performed in two different renormalization schemes for γ5, and the compatibility of the results obtained in the two schemes is verified. The scaleand scheme-invariant combinations of spectral 2–point functions and corresp...

Strong isospin-breaking (IB) effects in CP-even and CP-odd K → ππ decays are computed to next-to-leading order (NLO) in the chiral expansion. The impact of these corrections on the magnitude of the ∆I = 1/2 Rule and on the size of the IB correction, ΩIB, to the gluonic penguin contribution to ǫ /ǫ are discussed. In the presence of IB, the standard isospin decomposition of the K → ππ, K → ππ, ππ...

Recently, a systematic analysis of η0 pole contributions to radiative K decays was performed in the context of large Nc ChPT, in order to better understand the role of gluonic penguin operators in K → ππ transitions1. In this note, we emphasize some aspects of this study, in view of the forthcoming new experimental information on K+ → π+γγ by the NA48 Collaboration2. A number of issues, like th...