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arXiv · 0707.3424

IR-Improved DGLAP Theory: Kernels, Parton Distributions, Reduced Cross Sections

B. F. L. Ward
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Abstract

It is shown that exact, amplitude-based resummation allows IR-improvement of the usual DGLAP theory. This results in a new set of kernels, parton distributions and attendant reduced cross sections, so that the QCD perturbative result for the respective hadron-hadron or lepton-hadron cross section is unchanged order-by-order in $α_s$ at large squared-momentum transfers. We compare these new objects with their usual counter-parts and illustrate the effects of the IR-improvement in some phenomenological cases of interest with an eye toward precision applications in LHC physics scenarios.

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B. F. L. Ward. 2007-10-27. IR-Improved DGLAP Theory: Kernels, Parton Distributions, Reduced Cross Sections. https://doi.org/10.1016/j.aop.2007.11.010

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