Logo image
Measurement of diffractive photoproduction of vector mesons at large momentum transfer at HERA
Journal article   Peer reviewed

Measurement of diffractive photoproduction of vector mesons at large momentum transfer at HERA

ZEUS Collaboration, J Repond and U Mallik
The European physical journal. C, Particles and fields, Vol.14(2), pp.213-238
05/01/2000
DOI: 10.1007/s100520000374
url
https://digitalcommons.andrews.edu/pubs/2453View
Open Access

Abstract

Elastic and proton-dissociative photoproduction of rho(0), phi and J/psi vector mesons (gamma p --> Vp, gamma p --> VN, respectively) have been measured in e(+)p interactions at HERA up to -t = 3 GeV2, where t is the four-momentum transfer squared at the photon-vector-meson vertex. The analysis is based on a data sample in which photoproduction reactions were tagged by detection of the scattered positron in a special-purpose calorimeter. This limits the photon virtuality, Q(2), to values less than 0.01 GeV2, and selects a gamma p average center-of-mass energy of (W) = 94 GeV. Results for the differential cross sections, d sigma/dt, for rho(0), phi and J/psi mesons are presented and compared to the results of recent QCD calculations. Results are also presented for the t-dependence of the pion-pair invariant-mass distribution in the rho(0) mass region and of the spin-density matrix elements determined from the decay-angle distributions. The Pomeron trajectory has been derived from measurements of the W dependence of the elastic differential cross sections d sigma/dt for both rho(0) and phi mesons.
Physical Sciences Physics Physics, Particles & Fields Science & Technology

Details

Metrics

Logo image