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arXiv · hep-ph/9703424

Towards systematic near-threshold calculations in perturbative QFT

Fyodor V. Tkachov
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Abstract

For any near-threshold asymptotic regime and for any Feynman diagram (involving loop and/or phase space integrals), a systematic prescription for explicitly constructing all-logs, all-powers (all-twists) expansions in perfectly factorized form with explicit integrals for coefficients, is presented. The distribution-theoretic nature of the method of asymptotic operation employed allows treatment of totally exclusive phase space in the same manner as loop integrals.

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Fyodor V. Tkachov. 1998-11-07. Towards systematic near-threshold calculations in perturbative QFT. https://doi.org/10.1016/s0370-2693(97)01017-4

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