Forward – Backward Asymmetry in B → X s l + l − at the NNLL Level
نویسندگان
چکیده
We report the results of a new calculation of soft-gluon corrections in B → Xsll 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. 1 Work supported by the U.S. Department of Energy (DOE). 2 Heisenberg Fellow.
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