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Power corrections to B\to X_u l ν(X_sγ) decay spectra in the "shape-function" region

M. Beneke·F. Campanario·T. Mannel·B. D. Pecjak
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Abstract

Using soft-collinear effective theory (SCET), we examine the 1/m_b corrections to the factorization formulas for inclusive semi-leptonic B decays in the endpoint region, where the hadronic final state consists of a single jet. At tree level, we find a new contribution from four-quark operators that was previously assumed absent. Beyond tree level many sub-leading shape-functions are needed to correctly describe the decay process.

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M. Beneke, F. Campanario, T. Mannel, B. D. Pecjak. 2005-06-07. Power corrections to B\to X_u l ν(X_sγ) decay spectra in the "shape-function" region. https://doi.org/10.1088/1126-6708%2F2005%2F06%2F071

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