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Forward--Backward Asymmetry in B -> X_s l^+ l^- at the NNLL Level

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

We report the results of a new calculation of soft-gluon corrections in B -> X_s l^+ l^- decays. In particular, we present the first calculation of bremsstrahlung and corresponding virtual terms to the lepton forward-backward asymmetry, which allows us to systematically include all contributions to this observable beyond the lowest non-trivial order. The new terms are important, for instance the position of the zero of the asymmetry receives corrections of O(10%). Using a different method, we also provide an independent check of recently published results on bremsstrahlung and infrared virtual corrections to the dilepton-invariant mass distribution.

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A. Ghinculov, T. Hurth, G. Isidori, Y. -P. Yao. 2002-09-19. Forward--Backward Asymmetry in B -> X_s l^+ l^- at the NNLL Level. https://doi.org/10.1016/s0550-3213(02)00998-7

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