Prompt charmonia production and polarization at LHC in the NRQCD with $k_T$-factorization. Part III: $J/\psi$ meson

Abstract

In the framework of $k_T$-factorization approach, the production and polarization of prompt $J/\psi$ mesons at the LHC energies is studied. Our consideration is based on the non-relativistic QCD formalism for bound states and off-shell amplitudes for hard partonic subprocesses. Both the direct production mechanism and feed-down contributions from ${\chi }_c$ and $\psi (2S)$ decays are taken into account. The transverse momentum dependent (or unintegrated) gluon densities in a proton were derived from Ciafaloni-Catani-Fiorani-Marchesini evolution equation or, alternatively, were chosen in accordance with Kimber-Martin-Ryskin prescription. The non-perturbative color-octet matrix elements were first deduced from the fits to the latest CMS data on $J/\psi$ transverse momentum distributions and then applied to describe the ATLAS and LHCb data on $J/\psi$ production and polarization at $\sqrt{s}=7$, $8$ and $13$ TeV. We perform an estimation of polarization parameters ${\lambda }_{\theta }$, ${\lambda }_{\varphi }$ and ${\lambda }_{\theta \varphi }$ which determine $J/\psi$ spin density matrix and demonstrate that treating the soft gluon emission as a series of explicit color-electric dipole transitions within NRQCD leads to unpolarized $J/\psi$ production at high transverse momenta, that is in qualitative agreement with the LHC data.

23 pages, 14 figures. arXiv admin note: substantial text overlap with arXiv:1508.05480

References in corpus (15)

• Parton distributions for the LHC
• J/psi (psi') production at the Tevatron and LHC at O(α_s^4v^4) in nonrelativistic QCD
• Extending the Higgs sector: an extra singlet
• Reconciling J/psi production at HERA, RHIC, Tevatron, and LHC with NRQCD factorization at next-to-leading order
• Polarization for Prompt J/psi, psi(2s) production at the Tevatron and LHC
• Upsilon production at the Tevatron and the LHC
• Measurement of forward $J/\psi$ production cross-sections in $pp$ collisions at $\sqrt{s}=13$ TeV
• Quarkonium production in the LHC era: a polarized perspective
• Charmonium Production at High Energy in the k_T-Factorization Approach
• Measurement of J/psi and psi(2S) prompt double-differential cross sections in pp collisions at sqrt(s) = 7 TeV
• Measurement of $\psi (2S)$ polarisation in $pp$ collisions at $\sqrt{s}=7$ TeV
• Prompt charmonia production and polarization at LHC in the NRQCD with kt-factorization. Part I: psi(2S) meson
• Measurement of the production cross-section of $\psi (2S)\to J/\psi (\to {\mu }^{+}{\mu }^{-}){\pi }^{+}{\pi }^{-}$ in $pp$ collisions at $\sqrt{s}=7$ TeV at ATLAS
• Inclusive production of $J/\psi$ meson in proton-proton collisions at BNL RHIC
• Prompt charmonia production and polarization at LHC in the NRQCD with kt-factorization. Part II: ${\chi }_c$ mesons

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