We re-estimate the decay branching ratio of Bs → 2γ through D + s D − s and D∗+ s D ∗− s intermediate states, in the effective Lagrangian approach. We find that the branching ratio does not exceed a few times 10−7, contrary to the result recently claimed in the literature. PACS numbers: 13.25.Hw Typeset using REVTEX

In a recently proposed extension of the Standard Model with a compact extra dimension of size R we compute the leading corrections, of relative order (mtR) 2, to the Branching Ratio BR(B → Xsγ). For R = (370 ± 80GeV )−1 the branching ratio is increased in a significant way relative to the SM, although not at the level of being inconsistent with present measurements.

We calculate the next-to-leading corrections to the branching ratio of exclusive B → Kγ decay. The renormalization scale dependence is reduced compared to the leading logarithmic result but there remains a dependence on a cutoff parameter of the hadronic model. The calculated corrections increase the predicted branching ratio by about 10%, but it remains in agreement with the experimental value.

The CKM collaboration is proposing to measure the branching ratio of the rare K decay K + → π + ν ¯ ν at the Main Injector at Fermilab. Our goal is to be able to observe ≃ 100 events, for a Standard Model branching ratio of ≃ 1. 10 −10. This implies that we must be able to reduce the background to a few events at a reasonable cost.

We present a branching ratio measurement for the beta decay of neutral Cascade hyperon, 0 ! + e e , using the KTeV detector at Fermilab. We used the principal decay mode of 0 ! 0 where ! p , as the ux normalization mode. The status of the measurement of the ratio of the axial-vector to vector coupling (g1/f1) for the Cascade beta decay will also be discussed. Furthermore, we present the prelimi...