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Factorization in leptonic radiative B -> gamma eνdecays

Enrico Lunghi·Dan Pirjol·Daniel Wyler
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Abstract

We discuss factorization in exclusive radiative leptonic B->γeνdecays using the soft-collinear effective theory. The form factors describing these decays can be expanded in a power series in Lambda/E_γwith E_γthe photon energy. We write down the most general operators in the effective theory which contribute to the form factors at leading order in Lambda_QCD/E_γ, proving their factorization into hard, jet and soft contributions, to all orders in alpha_s.

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Enrico Lunghi, Dan Pirjol, Daniel Wyler. 2002-12-15. Factorization in leptonic radiative B -> gamma eνdecays. https://doi.org/10.1016/s0550-3213(02)01032-5

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