Completing the Calculation of BLM corrections to B̄ → X s γ
نویسنده
چکیده
Perturbative O(αs) corrections to B(B̄ → Xsγ) in the BLM approximation receive contributions from two-, threeand four-body final states. While all the two-body results are well established by now, the other ones have remained incomplete for several years. Here, we calculate the last contribution that has been missing to date, namely the one originating from interference of the current-current and gluonic dipole operators (K (2)β0 18 and K (2)β0 28 ). Moreover, we confirm all the previously known results for BLM corrections to the photon energy spectrum that involve the current-current operators (e.g., K (2)β0 22 and K (2)β0 27 ). Finally, we also confirm the recent findings of Ferroglia and Haisch on self-interference of the gluonic dipole operator (K (2)β0 88 ).
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