The rare decay B --> X_s l^+ l^- to NNLL precision for arbitrary dilepton invariant mass

A. Ghinculov; T. Hurth; G. Isidori; Y. -P. Yao

doi:10.1016/j.nuclphysb.2004.02.028

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arXiv · hep-ph/0312128

The rare decay B --> X_s l^+ l^- to NNLL precision for arbitrary dilepton invariant mass

A. Ghinculov·T. Hurth·G. Isidori·Y. -P. Yao

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Abstract

We present a new phenomenological analysis of the inclusive rare decay $B \to X_s \ell^+\ell^-$. In particular, we present the first calculation of the NNLL contributions due to the leading two-loop matrix elements, evaluated for arbitrary dilepton invariant mass. This allows to obtain the first NNLL estimates of the dilepton mass spectrum and the lepton forward-backward asymmetry in the high $ M^2_{\ell^+ \ell^-}$ region, and to provide an independent check of previously published results in the low $ M^2_{\ell^+ \ell^-}$ region. The numerical impact of these NNLL corrections in the high-mass region ($ M^2_{\ell^+ \ell^-} > 14.4 GeV^2$) amounts to -13% in the integrated rate, and leads to a reduction of the scale uncertainty to $\pm 3%$. The impact of non-perturbative contributions in this region is also discussed in detail.

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A. Ghinculov, T. Hurth, G. Isidori, Y. -P. Yao. 2004-02-24. The rare decay B --> X_s l^+ l^- to NNLL precision for arbitrary dilepton invariant mass. https://doi.org/10.1016/j.nuclphysb.2004.02.028

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