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NNLL QCD Corrections to the Decay $B \to X_s \ell^+ \ell^-$

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

We briefly discuss the status of the NNLL QCD calculations in the inclusive rare B decay $B \to X_s \ell^+ \ell^-$. Two important ingredients, the two-loop matrix elements of the four quark operator ${\cal O}_2$ and the bremsstrahlung contributions, were quite recently finalised. The new contributions significantly improve the sensitivity of the inclusive decay $B \to X_s l^+ l^-$ decay in testing extensions of the standard model in the sector of flavour dynamics; for instance the two-loop calculation cuts the low- scale uncertainty in half and the bremsstrahlung calculation leads to a 10% shift of the position of the zero of the forward- backward asymmetry.

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A. Ghinculov, T. Hurth, G. Isidori, Y. -P. Yao. 2002-11-20. NNLL QCD Corrections to the Decay $B \to X_s \ell^+ \ell^-$. https://doi.org/10.1016/s0920-5632(03)80185-8

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