ar X iv : h ep - p h / 99 05 50 4 v 1 2 7 M ay 1 99 9 On the Long Distance Contribution to the B s → γγ Decay in the Effective Lagrangian Approach
نویسنده
چکیده
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
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