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arXiv · 1908.02812

Reevaluating Uncertainties in $\bar B\to X_s\gamma$ Decay

Ayesh Gunawardana·Gil Paz
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Abstract

The rare decay $\bar B\to X_s\gamma$ 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 $Q_{7\gamma}$ in the effective weak Hamiltonian. One of the three leading contributions, $Q^q_1-Q_{7\gamma}$, 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 $\bar B\to X_s\gamma$ total rate and CP asymmetry.

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Ayesh Gunawardana, Gil Paz. 2019-08-07. Reevaluating Uncertainties in $\bar B\to X_s\gamma$ Decay. https://doi.org/10.1007/jhep11(2019)141

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