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arXiv · 1108.2856

Prompt J/Psi production at LHC: new evidence for the kt-factorization

S. P. Baranov·A. V. Lipatov·N. P. Zotov
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Abstract

In the framework of the kt-factorization approach, the production and polarization of prompt J/Psi mesons in pp collisions at the LHC energy 7 TeV is studied. Both the direct production mechanism as well as feed-down contributions from chic1, chic2 and psi' decays are taken into account. Our consideration is based on the color singlet model supplemented with the off-shell matrix elements for the corresponding partonic subprocesses. The unintegrated gluon densities in a proton are determined using the CCFM evolution equation as well the Kimber-Martin-Ryskin prescription. We compare our numerical predictions with the first experimental data taken by the CMS, ATLAS and LHCb collaborations. The estimation of all polarization parameters which determine J/Psi spin density matrix is performed.

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S. P. Baranov, A. V. Lipatov, N. P. Zotov. 2011-08-14. Prompt J/Psi production at LHC: new evidence for the kt-factorization. https://doi.org/10.1103/physrevd.85.014034

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