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Journal of High Energy Physics

, 2018:57 | Cite as

J/ψ polarization in the CGC+NRQCD approach

  • Yan-Qing Ma
  • Tomasz StebelEmail author
  • Raju Venugopalan
Open Access
Regular Article - Theoretical Physics

Abstract

We compute the J/ψ polarization observables λθ, λϕ, λθϕ in a Color Glass Condensate (CGC) + nonrelativistic QCQ (NRQCD) formalism that includes contributions from both color singlet and color octet intermediate states. Our results are compared to low pT data on J/ψ polarization from the LHCb and ALICE experiments on proton-proton collisions at center-of-mass energies of \( \sqrt{s}=7 \) TeV and 8 TeV. Our CGC+NRQCD computation provides a better description of data for pT ≤ 15 GeV relative to extant next-to-leading (NLO) calculations within the collinear factorization framework. These results suggest that higher order computations in the CGC+NRQCD framework have the potential to greatly improve the accuracy of extracted values of the NRQCD universal long distance matrix elements.

Keywords

QCD Phenomenology 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  • Yan-Qing Ma
    • 1
    • 2
    • 3
  • Tomasz Stebel
    • 4
    • 5
    Email author
  • Raju Venugopalan
    • 5
  1. 1.School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijingChina
  2. 2.Center for High Energy PhysicsPeking UniversityBeijingChina
  3. 3.Collaborative Innovation Center of Quantum MatterBeijingChina
  4. 4.Institute of Nuclear Physics PANKrakówPoland
  5. 5.Physics DepartmentBrookhaven National LaboratoryUptonU.S.A.

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