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arXiv · 1310.7893

LHC soft physics and TMD gluon density at low x

Abstract

We study the unintegrated, or transverse momentum dependent (TMD) gluon distribution obtained from the best description of the LHC data on the inclusive spectra of hadrons produced in the mid-rapidity region and low transverse momenta at starting scale Q0^2 = 1 GeV^2. To extend this gluon density at higher Q^2 we apply the Catani-Ciafoloni-Fiorani-Marchesini (CCFM) evolution equation. The influence of the initial (starting) non-perturbative gluon distribution is studied. The application of the obtained gluon density to the analysis of the ep deep inelastic scattering allows us to get the results which describe reasonably well the H1 and ZEUS data on the longitudinal proton structure function FL(x,Q^2). So, the connection between the soft processes at LHC and small x physics at HERA has been confirmed and extended to a wide kinematical region.

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BibTeXRIS

A. V. Lipatov, G. I. Lykasov, N. P. Zotov. 2013-10-29. LHC soft physics and TMD gluon density at low x. https://doi.org/10.1103/physrevd.89.014001

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