Adler function from R^e+e- (s) measurements: experiments vs QCD theory

Abstract

An experimentally motivated QCD analysis of the behaviour of the Adler D-function in the Euclidian region is described. It is stressed that by taking account of b-quark mass-dependent α 2 s -effects one obtains better agreement between theoretical predictions and experimentally motivated behaviour of the D-function at large Euclidian momentum transfer. A more detailed analysis of QCD predictions, including information on quark and gluon condensates, requires more precise data on e + e − → hadrons, particularly in the energy regions E < M J/Ψ