QCD Sum Rule Analysis of the Subleading
نویسندگان
چکیده
We present a QCD sum rule calculation of the spin-symmetry violating universal function χ2(v · v′), which appears at order 1/mQ in the heavy quark expansion of meson form factors. This function vanishes in the standard approximation, where radiative effects are neglected. For the first time, the complete set of diagrams arising at order αs is evaluated. In particular, we find χ2(1) = −(3.8± 0.4)% at zero recoil, indicating that 1/mQ corrections induced by the chromo-magnetic moment operator are small.
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