Abstract
We perform a finite energy sum rule analysis of the flavor ud two-point V–A current correlator, ΔΠ(Q2). The analysis, which is performed using both the ALEPH and OPAL databases for the V–A spectral function, Δρ, allows us to extract the dimension six V–A OPE coefficient, a6, which is related to the matrix element of the electroweak penguin operator, Q8, by chiral symmetry. The result for a6 leads directly to the improved (chiral limit) determination ϵ′/ϵ=(−15.0±2.7)×10−4. Determination of higher dimension OPE contributions also allows us to perform an independent test using a low-scale constrained dispersive analysis, which provides a highly nontrivial consistency check of the results.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.