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Light-cone sum rules for the heavy-to-light transition in the effective theory

Jong-Phil Lee
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Abstract

Heavy-to-light weak form factor is calculated using the light-cone sum rule (LCSR)in the framework of soft-collinear effective theory (SCET). There are spin-symmetric and spin-nonsymmetric contributions. Leading order spin-symmetric contribution corresponds to the ''soft overlap'' where some of the partons carry very small momentum. The next-to-leading order spin-symmetric and spin-nonsymmetric parts are characterized by a collinear gluon exchange with the spectator quark. We reproduce the full theory LCSR results and give comments on recent LCSR in SCET.

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Jong-Phil Lee. 2005-10-22. Light-cone sum rules for the heavy-to-light transition in the effective theory. https://doi.org/10.1016/j.physletb.2005.10.055

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