Angular and current-target correlations in deep inelastic scattering at HERA

Correlations between charged particles in deep inelastic scattering have been studied in the Breit frame with the ZEUS detector at HERA using an integrated luminosity of 6.4 pb. Short-range correlations are analysed in terms of the angular separation between current-region particles within a cone centred around the virtual photon axis. Long-range correlations between the current and target regions have also been measured. The data support predictions for the scaling behaviour of the angular correlations at high and for anti-correlations between the current and target regions over a large range in and in the Bjorken scaling variable x. Analytic QCD calculations and Monte Carlo models correctly describe the trends of the data at high , but show quantitative discrepancies. The data show differences between the correlations in deep inelastic scattering and annihilation. Received: 18 May 1999 / Published online: 3 November 1999