Forward–backward asymmetry in B→Xsℓ+ℓ− at the NNLL level Original Research Article

We report the results of a new calculation of soft-gluon corrections in B→Xsℓ+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.