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Effects of next-to-leading order DGLAP evolution on generalized parton distributions of the proton and deeply virtual Compton scattering at high energy

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 نشر من قبل Vadim Guzey
 تاريخ النشر 2017
  مجال البحث
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 تأليف Hamzeh Khanpour




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We studied the effects of NLO $Q^2$ evolution of generalized parton distributions (GPDs) using the aligned-jet model for the singlet quark and gluon GPDs at an initial evolution scale. We found that the skewness ratio for quarks is a slow logarithmic function of $Q^2$ reaching $r^S=1.5-2$ at $Q^2=100$ GeV$^2$ and $r^g approx 1$ for gluons in a wide range of $Q^2$. Using the resulting GPDs, we calculated the DVCS cross section on the proton in NLO pQCD and found that this model in conjunction with modern parameterizations of proton PDFs (CJ15 and CT14) provides a good description of the available H1 and ZEUS data in a wide kinematic range.

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