Exclusive electroproduction of and mesons at HERA
J. Breitweg - et al.
Received: 20 August 1998 / Published online: 14 January 1999
Exclusive production of and mesons in e+p collisions has been studied with the ZEUS detector in the kinematic range 0.25 < Q2 < 50 , 20 < W < 167 GeV for the data and 2 < Q2 < 40 , 50 < W < 150 GeV for the data. Cross sections for exclusive and production have been measured as a function of Q2, W and t. The spin-density matrix elements r0400, r11-1 and Rehave been determined for exclusive production as well as r0400 and r041-1 for exclusive production. The results are discussed in the context of theoretical models invoking soft and hard phenomena.