MASS CORRECTIONS TO THE VECTOR CURRENT CORRELATOR

Three-loop QCD corrections to the vector current correlator are consid ered. The large momentum procedure is applied in order to evaluate mas s corrections up to order (m(2)/q(2))(6). The inclusion of the first s even terms to the ratio R = sigma(e(+)e(-) --> hadrons)/sigma(e(+)e(-) --> mu(+)mu(-)) leads to reliable predictions from the high-energy re gion down to relatively close to threshold. (C) 1997 Elsevier Science B.V. PACS: 12.38.-t; 12.38.Bx; 13.65.+i; 13.85.Lg.