The role of initial gluon emission in double $J/\psi$ production at central rapidities

Abstract

We consider the process of double $J/\psi$ production in $pp$ collisions at the LHC in the framework of $k_T$-factorization approach. We focus on the gluon fragmentation mechanism which is related to multiple gluon emission in the initial state. The initial state emission is treated according to Catani-Ciafaloni-Fiorani-Marchesini evolution equation, and applies to both single and double parton scattering cases. We show the importance of fragmentation contributions to $J/\psi$ pair production and perform a comparison between theoretical predictions and the latest ATLAS data collected at $\sqrt{s}=8$ TeV. We find that the effects of multiple gluon emission are essential for both single- and multiparton interaction processes. Finally, we highlight the problem of correct choice of the factorization scale with respect to numerical stability of the calculations and the consistency with non-collinear evolution equations.

References in corpus (11)

• J/psi (psi') production at the Tevatron and LHC at O(α_s^4v^4) in nonrelativistic QCD
• Polarization for Prompt J/psi, psi(2s) production at the Tevatron and LHC
• The four jet production at LHC and Tevatron in QCD
• QCD radiative corrections to ${\chi }_{cJ}$ production at hadron colliders
• Measurement of the prompt $J/\psi$ pair production cross-section in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
• CASCADE3 A Monte Carlo event generator based on TMDs
• Study of hard double-parton scattering in four-jet events in $pp$ collisions at $\sqrt{s}=7$ TeV with the ATLAS experiment
• Complete Nonrelativistic-QCD Prediction for Prompt Double $J/\psi$ Hadroproduction
• Production of ${\chi }_c$- and ${\chi }_b$-mesons in high energy hadronic collisions
• Phenomenological NLO analysis of eta(c) production at the LHC in the collider and fixed-target modes
• Revisiting the production of $J/\psi$ pairs at the LHC