Five-loop vacuum polarization in pQCD: O(m(q)(2)alpha(4)(s)n(f)(2)) contribution

摘要

We present the analytical calculation of the contribution of order m(q)(2)alpha(s)(4)n(f)(2) to the absorptive part of the vacuum polarization function of vector cuffents. This term constitutes an important gauge-invariant part of the full O(m(q)(2)alpha(s)(4)) coffection to the total cross-section of e(+)e(-) annihilation into hadrons. The results are compared to predictions following from various optimization schemes. (C) 2003 Published by Elsevier Science B.V. References: 55