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A New 5 Flavour NLO Analysis and Parametrizations of Parton Distributions of the Real Photon

F. Cornet·P. Jankowski·M. Krawczyk
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Abstract

New, radiatively generated, NLO quark (u,d,s,c,b) and gluon densities in a real, unpolarized photon are presented. We perform three global fits, based on the NLO DGLAP evolution equations for Q^2>1 GeV^2, to all the available structure function F_2^gamma(x,Q^2) data. As in our previous LO analysis we utilize two theoretical approaches. Two models, denoted as FFNS_{CJK}1 & 2 NLO, adopt the so-called Fixed Flavour-Number Scheme for calculation of the heavy-quark contributions to F_2^gamma(x,Q^2), the CJK NLO model applies the ACOT(chi) scheme. We examine the results of our fits by a comparison with the LEP data for the Q^2 dependence of the F_2^gamma, averaged over various x-regions, and the F_2,c^gamma. Grid parametrizations of the parton densities for all fits are provided.

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F. Cornet, P. Jankowski, M. Krawczyk. 2004-04-07. A New 5 Flavour NLO Analysis and Parametrizations of Parton Distributions of the Real Photon. https://doi.org/10.1103/physrevd.70.093004

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