The Weak Ope and Dimension - Eight Operators
نویسنده
چکیده
We discuss recent work which identifies a potential flaw in standard treatments of weak decay amplitudes , including that of ǫ ′ /ǫ. The point is that (contrary to conventional wisdom) dimension-eight operators contribute to weak amplitudes at order G F αs and without 1/M 2 W suppression. The effect of dimension-eight operators is estimated to be at the 100% level in a sum rule determination of the operator Q (6) 7 for µ = 1.5 GeV, suggesting that presently available values of µ are too low to justify the neglect of these effects.
منابع مشابه
Dimension-eight operators in the weak OPE
We argue that there is a potential flaw in the standard treatment of weak decay amplitudes, including that of ′/ . We show that (contrary to conventional wisdom) dimension-eight operators do contribute to weak amplitudes, at order GF αs and without 1/M2 W suppression. We demonstrate the existence of these operators through the use of a simple weak hamiltonian. Their contribution appears in diff...
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