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arXiv · 2502.16461

Production of $S$-wave charmonia in the soft gluon resummation approach using the NRQCD

Abstract

In this article, we study the $S-$wave charmonium production at the small transverse momenta in the transverse momentum dependent (TMD) parton model (PM), as it is formulated in the soft gluon resummation (SGR) approach , using the nonrelativistic quantum chromodynamics (NRQCD) as the model of the heavy quarkonium hadronization. To extend the scope of the calculation to the phenomenologically important region of intermediate transverse momenta, we use the inverse-error weighting (InEW) matching scheme to combine the TMD PM predictions with the results of the collinear PM (CPM) fixed-order calculations, which are applicable at the large transverse momenta. We predict the direct $\eta_c$ and the prompt $J/\psi$ production cross sections and transverse momentum spectra in proton-proton collisions at the LHC, RHIC, AFTER and NICA energies. Predictions for the polarized $J/\psi$ production processes are also presented.

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Vladimir Saleev, Kirill Shilyaev. 2025-02-23. Production of $S$-wave charmonia in the soft gluon resummation approach using the NRQCD. https://doi.org/10.1142/s0217732325501457

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