Journal of High Energy Physics

, 2018:179 | Cite as

Probing axial quark generalized parton distributions through exclusive photoproduction of a γπ± pair with a large invariant mass

  • G. Duplančić
  • K. Passek-Kumerički
  • B. Pire
  • L. Szymanowski
  • S. WallonEmail author
Open Access
Regular Article - Theoretical Physics


Exclusive photoproduction of a γπ± pair in the kinematics where the pair has a large invariant mass and the final nucleon has a small transverse momentum is described in the collinear factorization framework. The scattering amplitude is calculated at leading order in αs and the differential cross sections for the process are estimated in the kinematics of the JLab 12-GeV experiments. The order of magnitude of the predicted cross-sections seems sufficient for a dedicated experiment to be performed. The process turns out to be very sensitive to the axial generalized parton distribution combination \( {\tilde{H}}_u-{\tilde{H}}_d \).


QCD Phenomenology 


Open Access

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  • G. Duplančić
    • 1
  • K. Passek-Kumerički
    • 1
  • B. Pire
    • 2
  • L. Szymanowski
    • 3
  • S. Wallon
    • 4
    • 5
    Email author
  1. 1.Theoretical Physics Division, Rudjer Bošković InstituteZagrebCroatia
  2. 2.Centre de Physique Théorique, Ecole polytechnique, CNRS, Université Paris-SaclayPalaiseauFrance
  3. 3.National Center for Nuclear Research (NCBJ)WarsawPoland
  4. 4.Laboratoire de Physique Théorique, UMR 8627, CNRS, Univ. Paris-Sud, Université Paris-SaclayOrsay CedexFrance
  5. 5.Sorbonne Université, Faculté de PhysiqueParis Cedex 05France

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