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arXiv · 0712.0178

Systematic errors of transition form factors extracted by means of light-cone sum rules

Wolfgang Lucha·Dmitri Melikhov·Silvano Simula
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Abstract

This talk presents results of our study of heavy-to-light transition form factors extracted with the help of light-cone sum rules. We employ a model with scalar particles interacting via massless-boson exchange and study the heavy-to-light correlator, relevant for the extraction of the transition form factor. We calculate this correlator in two different ways: by making use of the Bethe-Salpeter wave function of the light bound state and by making use of the light-cone expansion. This allows us to calculate the full correlator and separately the light-cone contribution to it. In this way we show that the off-light cone contributions are not suppressed compared to the light-cone one by any large parameter. Numerically, the difference between the value of the form factor extracted from the full correlator and from the light-cone contribution to this correlator is found to be about 20-30% in a wide range of masses of the particles involved in the decay process.

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Wolfgang Lucha, Dmitri Melikhov, Silvano Simula. 2007-12-02. Systematic errors of transition form factors extracted by means of light-cone sum rules. https://arxiv.org/abs/0712.0178

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