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arXiv · hep-ph/9604438

The Chromomagnetic Dipole Operator and the B Semileptonic Branching Ratio

M. Ciuchini·E. Gabrielli·G. F. Giudice
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Abstract

We consider the possibility of having a large branching ratio for the decay $b\to s g$ coming from an enhanced Wilson coefficient of the chromomagnetic dipole operator. We show that values of $BR(b\to s g)$ up to $\sim 10\%$ or more are compatible with the constraints coming from the CLEO experimental results on $BR(B\to X_sγ)$ and $BR(B\to X_sϕ)$. Such large values can reconcile the predictions of both the semileptonic branching ratio and the charm counting with the present experimental results. We also discuss a supersymmetric model with gluino-mediated flavour violations, which can account for such large values of $BR(b\to s g)$.

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M. Ciuchini, E. Gabrielli, G. F. Giudice. 1996-05-03. The Chromomagnetic Dipole Operator and the B Semileptonic Branching Ratio. https://doi.org/10.1016/s0370-2693(96)01168-9

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