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Five-loop vacuum polarization in pQCD: O(m_q^2α_s^4 n_f^2) contribution

P. A. Baikov·K. G. Chetyrkin·J. H. Kühn
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Abstract

We present the analytical calculation of the contribution of order m_q^2 α_s^4 n_f^2 to the absorptive part of the vacuum polarization function of vector currents. This term constitutes an important gauge-invariant part of the full O(m_q^2 alpha_s^4) correction to the total cross-section of e^+ e^- annihilation into hadrons. The results are compared to predictions following from various optimization schemes.

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P. A. Baikov, K. G. Chetyrkin, J. H. Kühn. 2003-03-11. Five-loop vacuum polarization in pQCD: O(m_q^2α_s^4 n_f^2) contribution. https://doi.org/10.1016/s0370-2693(03)00186-2

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