Scale influence on the energy dependence of photon - proton cross-sections

Collaboration
Oct, 1996
13 pages
Published in:
  • Phys.Lett.B 392 (1997) 234-242
e-Print:
Report number:
  • DESY-96-224
Experiments:

Citations per year

1997199819992000412
Abstract:
The scale dependence of the evolution of photoproduction cross sections with the photon-proton centre of mass energy W is studied using low Q~2 < 0.01 GeV~2 e~+p interactions collected by the H1 experiment at HERA. The value of the largest transverse momentum of a charged particle in the photon fragmentation region is used to define the hard scale. The slope of the WW dependence of the cross section is observed to increase steeply with increasing transverse momentum. The result is compared to measurements of the Q~2 evolution of the W dependence of the virtual photon-proton cross section. Interpretations in terms of QCD and in terms of Regge phenomenology are discussed.
Note:
  • 13 pages, latex, 3 Figures Report-no: DESY 96-224
  • positron p: colliding beams
  • exchange: one-photon
  • photon p: interaction
  • photon: fragmentation
  • hadron: photoproduction
  • cross section: energy dependence
  • charged particle: transverse momentum
  • quantum chromodynamics: perturbation theory
  • field theory: Regge
  • H1