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arXiv · hep-ph/0309155

Log(1/x) Gluon Distribution and Structure Functions in the Loop-Loop Correlation Model

Abstract

We consider the interaction of the partonic fluctuation of a scalar ``photon'' with an external color field to calculate the leading and next-to-leading order gluon distribution of the proton following the work done by Dosch-Hebecker-Metz-Pirner. We relate these gluon distributions to the short and long distance behavior of the cross section of an adjoint dipole scattering off a proton. The leading order result is a constant while the next-to-leading order result shows a ln(1/x) enhancement at small x. To get numerical results for the gluon distributions at the initial scale Q^2_0=1.8 GeV^2, we compute the adjoint dipole-proton cross section in the loop-loop correlation model. Quark distributions at the same initial scale are parametrized according to Regge theory. We evolve quark and gluon distributions to higher Q^2 values using the DGLAP equation and compute charm and proton structure functions in the small-x region for different Q^2 values.

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BibTeXRIS

H. -J. Pirner, A. I. Shoshi, G. Soyez. 2003-12-01. Log(1/x) Gluon Distribution and Structure Functions in the Loop-Loop Correlation Model. https://doi.org/10.1140/epjc%2Fs2003-01528-2

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