Journal of High Energy Physics

, 2011:152 | Cite as

Probing gluon and heavy-quark nuclear PDFs with γ + Q production in pA collisions

  • T. Stavreva
  • I. Schienbein
  • F. Arleo
  • K. Kovařík
  • F. Olness
  • J. Y. Yu
  • J. F. Owens
Open Access


We present a detailed phenomenological study of direct photon production in association with a heavy-quark jet in pA collisions at the Relativistic Heavy Ion Collider (RHIC) and at the Large Hadron Collider (LHC) at next-to-leading order in QCD. The dominant contribution to the cross-section comes from the gluon-heavy-quark (gQ) initiated subprocess, making γ + Q production a process very sensitive to both the gluon and the heavy-quark parton distribution functions (PDFs). Additionally, the RHIC and LHC experiments are probing complementary kinematic regions in the momentum fraction x carried by the target partons. Thus, the nuclear production ratio \( R_{pA}^{\gamma + Q} \) can provide strong constraints, over a broad x-range, on the poorly determined nuclear parton distribution functions which are extremely important for the interpretation of results in heavy-ion collisions.


QCD Phenomenology 


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© The Author(s) 2011

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

Authors and Affiliations

  • T. Stavreva
    • 1
  • I. Schienbein
    • 1
  • F. Arleo
    • 2
  • K. Kovařík
    • 3
  • F. Olness
    • 4
  • J. Y. Yu
    • 4
  • J. F. Owens
    • 5
  1. 1.Laboratoire de Physique Subatomique et de Cosmologie, UJF, CNRS/IN2P3, INPGGrenobleFrance
  2. 2.Laboratoire d’Annecy-le-Vieux de Physique Théorique (LAPTH), UMR5108Université de Savoie, CNRSAnnecy-le-Vieux cedexFrance
  3. 3.Karlsruhe Institute of Technology (KIT), Fakultät für PhysikInstitut für Theoretische Physik (IThP)KarlsruheGermany
  4. 4.Southern Methodist UniversityDallasU.S.A.
  5. 5.Florida State UniversityTallahasseeU.S.A.

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