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تسجيل مستخدم جديدReevaluating Uncertainties in $bar Bto X_sgamma$ Decay
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The rare decay $bar Bto X_sgamma$ is an important probe of physics beyond the standard model. The largest uncertainty on the total rate and the CP asymmetry arises from resolved photon contributions. These appear first at order $1/m_b$ and are related to operators other than $Q_{7gamma}$ in the effective weak Hamiltonian. One of the three leading contributions, $Q^q_1-Q_{7gamma}$, is described by a non-local function whose moments are related to HQET parameters. We use recent progress in our knowledge of these parameters to reevaluate the resolved photon contribution to $bar Bto X_sgamma$ total rate and CP asymmetry.
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