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

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 نشر من قبل Bennie F. L. Ward
 تاريخ النشر 2007
  مجال البحث
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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 $alpha_s$ 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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