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A sum rule from the shape function

U. Aglietti
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Abstract

We present a sum rule relating the electron energy spectrum and the hadron mass distribution in semileptonic b -> u decays close to threshold. The relation found is free from non-perturbative effects and the theoretical error is expected to be O(5%). An experimental confirmation of this prediction can provide a check of the basic assumptions at the root of the theory of the shape function.

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U. Aglietti. 2001-03-08. A sum rule from the shape function. https://arxiv.org/abs/hep-ph/0010251

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