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arXiv · 0812.3250

Dynamical parton distribution functions

Cristian Pisano
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Abstract

Recent measurements for F_2(x,Q^2) have been analyzed in terms of the `dynamical' and `standard' parton model approach at NLO and NNLO of perturbative QCD. Having fixed the relevant NLO and NNLO parton distributions, the implications and predictions for the longitudinal structure function F_L(x,Q^2) are presented. It is shown that the previously noted extreme perturbative NNLO/NLO instability of F_L(x,Q^2) is an artifact of the commonly utilized `standard' gluon distributions. In particular it is demonstrated that using the appropriate -- dynamically generated -- parton distributions at NLO and NNLO, F_L(x,Q^2) turns out to be perturbatively rather stable already for Q^2 \geq O(2-3 GeV^2).

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Cristian Pisano. 2008-12-17. Dynamical parton distribution functions. https://doi.org/10.1016/j.nuclphysbps.2009.03.111

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