QCD Condensates for the Light Quark V-A Correlator
نویسندگان
چکیده
We use the procedure of pinched-weight Finite Energy Sum Rules (pFESR) to determine the OPE coefficients a6, · · · , a16 of the flavor ud V-A correlator in terms of existing hadronic τ decay data. We show by appropriate weight choices that the error on the dominant d = 6 contribution, which is known to be related to the K → ππ matrix elements of the electroweak penguin operator in the chiral limit, may be reduced to below the ∼ 15% level. The values we obtain for OPE coefficients with d > 8 are shown to naturally account for the discrepancies between our results for the d = 6 and d = 8 terms and those of previous analyses, which were obtained neglecting d > 8 contributions. Typeset using REVTEX
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