2008/12/03 by B Collaboration, I. Abt, Mark Raymond Adams +97
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex
paper · pdf · doi:10.1140/epjc/s10052-009-0965-7
published as Eur.Phys.J.C60:525-542,2009 · 19 pages, 11 figures, 6 tables
arxiv created 2008/12/03 · openalex publication_date 2009/03/09 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/29
Measurements of the kinematic distributions of J/ψ mesons produced in p–C, p–Ti and p–W collisions at √(s)=41.6~GeV in the Feynman-x region −0.34<x F <0.14 and for transverse momentum up to p T =5.4 GeV/c are presented. The x F and p T dependencies of the nuclear suppression parameter, α, are also given. The results are based on 2.4×105 J/ψ mesons reconstructed in both the e + e − and μ + μ − decay channels. The data have been collected by the HERA-B experiment at the HERA proton ring of the DESY laboratory. The measurement explores the negative region of x F for the first time. The average value of α in the measured x F region is 0.981±0.015. The data suggest that the strong nuclear suppression of J/ψ production previously observed at high x F turns into an enhancement at negative x F .