Measurement of J/psi helicity distributions 
             in inelastic photoproduction at HERA

                   ZEUS  Collaboration 

                         Abstract 
  
The J/psi decay angular distributions have been measured in inelastic 
photoproduction in ep collisions with the ZEUS detector at HERA, using an
integrated luminosity of 468 pb^-1. The range in photon-proton centre-of-mass 
energy, W, was 50<W<180 GeV. The J/psi measons were identifies through their
decay into muon pairs. The polar and azimuthal angles of the mu+ were measured
in the J/psi rest frame and compared to theoretical predictions at leading
and next-to-leading order in QCD.