Photon-odderon interference in exclusive χ c charmonium production at the Electron-Ion Collider

• Published in: Physical review. D 2024-07, Vol.110 (1), Article 014025
• Main Authors: Benić, Sanjin, Dumitru, Adrian, Kaushik, Abhiram, Motyka, Leszek, Stebel, Tomasz
• Format: Article
• Language: English
• Subjects: Electron-Ion Collider; Gluons; Odderon; PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; QCD; Quantum chromodynamics; Quark model; Quarkonium
• ISSN: 2470-0010; 2470-0029
• DOI: 10.1103/PhysRevD.110.014025

Exclusive C = + 1 scalar, axial-vector, and tensor quarkonium production in high-energy electron-proton scattering requires a C -odd t -channel exchange of a photon or a three-gluon ladder. We derive the expressions for the corresponding amplitudes. The relative phase of the photon vs three-gluon exchange amplitudes is determined by the sign of the light-front matrix element of the eikonal color current operator d a b c J + a J + b J + c at moderate x , and is not affected by small- x QCD evolution. Model calculations predict constructive interference, which is particularly strong for momentum transfer | t | ∼ 1 GeV 2 where the cross section for χ c J production exceeds that for pure photon exchange by up to a factor of 4. Exclusive χ c J electroproduction at the high luminosity Electron-Ion Collider occurs with well measurable rates and measurements of these processes should find evidence for the perturbative odderon exchange. We also compute the total electroproduction cross section as a function of energy and provide first estimates of the number of χ c J events per month at the Electron-Ion Collider design luminosity.