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arXiv · hep-ph/0206100

QED box amplitude in heavy fermion production

J. Portoles·P. D. Ruiz-Femenia
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Abstract

We evaluate the two-photon box contribution to heavy fermion production in electron positron annihilation, that provides O(alpha^2) electromagnetic corrections to the Born cross section. The study of its non-relativistic expansion, relevant at energies close to the threshold of production, is also performed. We also verify that the threshold expansion of the one-loop integrals correctly reproduces our results, thus extending the applicability of this technique to heavy fermion production diagrams.

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J. Portoles, P. D. Ruiz-Femenia. 2002-06-11. QED box amplitude in heavy fermion production. https://doi.org/10.1140/epjc%2Fs2002-01030-5

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