2003/06/04 by H1 Collaboration, Å. Aktas, V. Andreev +97 · 62 citations
Physics and Astronomy · #Collider #HERA #Helicity #High-Energy Particle Collisions Research #Meson #Momentum transfer #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Perturbative QCD #Physics #Pomeron #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Scattering #hep-ex
paper · pdf · doi:10.1016/j.physletb.2003.06.056
published in Physics Letters B 568(3-4), 205-218 (Elsevier BV) · 21 pages, 6 figures and 6 tables
arxiv created 2003/06/04 · openalex publication_date 2003/07/22 · arxiv updated 2012/08/27 · openalex created_date 2022/05/12 · openalex updated_date 2026/08/05
The diffractive photoproduction of J/ψ mesons is measured with the H1 detector at the ep collider HERA using an integrated luminosity of 78 pb−1. The differential cross section dσ(γp→J/ψY)/dt is studied in the range 2<|t|<30 GeV2, where t is the square of the four-momentum transferred at the proton vertex. The cross section is also presented as a function of the photon–proton centre-of-mass energy Wγp in three t intervals, spanning the range 50<Wγp<200 GeV. A fast rise of the cross section with Wγp is observed for each t range and the slope for the effective linear Pomeron trajectory is measured to be α′=−0.0135±0.0074(stat.)±0.0051(syst.) GeV−2. The measurements are compared with perturbative QCD models based on BFKL and DGLAP evolution. The data are found to be compatible with s-channel helicity conservation.