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arXiv · hep-ph/0310029

CJK- Improved LO Parton Distributions in the Real Photon and Their Experimental Uncertainties

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

A new analysis of the radiatively generated, LO quark (u,d,s,c,b) and gluon densities in the real, unpolarized photon, improved in respect to our paper [1], is presented. We perform four new global fits to the experimental data for F2^gamma, two using a standard FFNS approach and two based on ACOT(chi) scheme [2], leading to the FFNS(CJK) and CJK models. We also present the analysis of the uncertainties of the new CJK 2 parton distributions due to the experimental errors, the very first such analysis performed for the photon. This analysis is based on the Hessian method, for a comparison for chosen cross-sections we use also the Lagrange method.

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F. Cornet, P. Jankowski, M. Krawczyk. 2003-10-02. CJK- Improved LO Parton Distributions in the Real Photon and Their Experimental Uncertainties. https://doi.org/10.1016/s0920-5632(03)02304-1

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