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Non-Valence Fock States in Heavy-to-Light Form Factors at Large Recoil

Bjorn O. Lange
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Abstract

We studied three-particle Fock state contributions to heavy-to-light form factors in the context of soft-collinear effective theory and found that they enter at leading power. These contributions are non-factorizable due to the appearance of endpoint singularities, however they do not violate spin-symmetry relations at leading power. In this talk I present their numerical estimation in a crude model in which the "soft overlap" contribution is cut off and find that they might lower the standard values for the form factors at maximum recoil significantly. Furthermore I briefly discuss the role of soft-collinear messenger modes in the region of soft overlap.

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Bjorn O. Lange. 2003-10-10. Non-Valence Fock States in Heavy-to-Light Form Factors at Large Recoil. https://doi.org/10.1140/epjcd%2Fs2003-03-219-9

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