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Next-to-leading order numerical calculations in Coulomb gauge

Michael Kramer·Davison E. Soper
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Abstract

Calculations of observables in quantum chromodynamics can be performed using a method in which all of the integrations, including integrations over virtual loop momenta, are performed numerically. We use the flexibility inherent in this method in order to perform next-to-leading order calculations for event shape variables in electron-positron annihilation in Coulomb gauge. The use of Coulomb gauge provides the potential to go beyond a purely order alpha_s^2 calculation by including, for instance, renormalon or parton showering effects. We expect that the approximations needed to include such effects at all orders in alpha_s will be simplest in a gauge in which unphysically polarized gluons do not propagate over long distances.

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Michael Kramer, Davison E. Soper. 2002-04-10. Next-to-leading order numerical calculations in Coulomb gauge. https://doi.org/10.1103/physrevd.66.054017

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