The 〈V V A〉 correlator at three loops in perturbative QCD
نویسندگان
چکیده
It is known that the correlator of one axial and two vector currents, that receives leading contributions through one-loop fermion triangle diagrams, is not modified by QCD radiative corrections at two loops. It was suggested that this non-renormalization of the 〈V V A〉 correlator persists in higher orders in perturbative QCD as well. To check this assertion, we compute the three-loop QCD corrections to the 〈V AA〉 correlator using the technique of asymptotic expansions. We find that these corrections do not vanish and that they are proportional to the QCD β-function.
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