Abstract
In this work, we present a thorough analysis of ηc(1S, 2S) quarkonia hadroproduction in k⊥-factorisation in the framework of the light-front potential approach for the quarkonium wave function. The off-shell matrix elements for the g*g*ηc(1S, 2S) vertices are derived. We discuss the importance of taking into account the gluon virtualities. We present the transverse momentum distributions of ηc for several models of the unintegrated gluon distributions. Our calculations are performed for four distinct parameterisations for the \( c\overline{c} \) interaction potential consistent with the meson spectra. We compare our results for ηc(1S) to measurements by the LHCb collaboration and present predictions for ηc(2S) production.
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Babiarz, I., Pasechnik, R., Schäfer, W. et al. Prompt hadroproduction of ηc(1S, 2S) in the kT-factorization approach. J. High Energ. Phys. 2020, 37 (2020). https://doi.org/10.1007/JHEP02(2020)037
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DOI: https://doi.org/10.1007/JHEP02(2020)037