6533b7d0fe1ef96bd125aa58
RESEARCH PRODUCT
First evidence of hard scattering processes in single tagged gamma-gamma-collisions
Delphi CollaborationEmilio Higón RodríguezRamón Cases RuizMaría Victoria Castillo GiménezJ. T. M. ChrinEduardo Cortina GilAntonio Ferrer SoriaJuan A. Fuster VerdúCarmen García GarcíaJuan José Gómez CadenasJuan José Hernández ReyJosé ÁNgel Hernando MorataCarlos Lacasta LlácerJosé Julio Lozano BahiloFernando Martínez VidalSalvador Martí GarcíaSergio Navas ConchaJosé Salt CairolsJuan Antonio Valls Ferrersubject
High Energy Physics::LatticeCol·lisions (Física nuclear)High Energy Physics::PhenomenologyHigh Energy Physics::ExperimentPartícules (Física nuclear)description
For the first time, multihadronic production from single tagged gammagamma collisions has been studied, where one of the scattered leptons was tagged at very low virtual photon absolute mass squared ( = 0.06GeV/(c2))2 ). Data collected during 1991 and 1992 in the DELPHI experiment at LEP are shown to agree well with predictions which included the non-perturbative vector meson dominance model in which the interacting photons are assumed to have converted into a vector meson (rho, omega or pi), a quark-parton model which describes direct photon interactions and a QCD-based model which considers the photon to have quark and gluon structure functions. Five different parametrizations of these structure functions were used and the predictions compared with the data. This study confirms recent results from no-tag experiments in requiring a QCD-based component to successfully describe the data, indicating that the photon has a significant partonic content.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1995-01-01 |