The B π form factor from light-cone sum rules in soft-collinear effective theory
نویسندگان
چکیده
Recently, we have derived light-cone sum rules for exclusive B-meson decays into light energetic hadrons from correlation functions within soft-collinear effective theory [1]. In these sum rules the short-distance scale refers to “hard-collinear” interactions with virtualities of order ΛQCDmb. Hard scales (related to virtualities of order mb) are integrated out and enter via external coefficient functions in the sum rule. Soft dynamics is encoded in light-cone distribution amplitudes for the B-meson, which describe both the factorizable and non-factorizable contributions to exclusive B-meson decay amplitudes. Factorization of the correlation function has been verified to oneloop accuracy. Thus, a systematic separation of hard, hard-collinear, and soft dynamics in the heavy-quark limit is possible.
منابع مشابه
Light-cone sum rules: A SCET-based formulation
We describe the construction of light-cone sum rules (LCSRs) for exclusive B-meson decays into light energetic hadrons from correlation functions within soft-collinear effective theory (SCET). As an example, we consider the SCET sum rule for the B → π transition form factor at large recoil, including radiative corrections from hard-collinear loop diagrams at first order in the strong coupling c...
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