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arXiv · hep-ph/0007196

Dimension-eight Operators in the Weak OPE

Vincenzo Cirigliano·John F. Donoghue·Eugene Golowich
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Abstract

We expose a potential flaw in standard treatments of weak decay amplitudes, including that of epsilon'/epsilon. We show that (contrary to conventional wisdom) dimension-eight operators do contribute to weak amplitudes, at order G_F alpha_s and without 1/M_W^2 suppression. We demonstrate the existence of these operators with a simple weak hamiltonian and proceed to discuss their contribution in a general context. We estimate the effect of dimension-eight operators to be at the 100% level in a sum rule determination of the operator O_7 for mu = 1.5 GeV, suggesting presently available values of mu are too low to justify neglect of these effects.

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Vincenzo Cirigliano, John F. Donoghue, Eugene Golowich. 2000-07-18. Dimension-eight Operators in the Weak OPE. https://doi.org/10.1088/1126-6708%2F2000%2F10%2F048

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