Exclusive ρ0 production in deep inelastic scattering at HERA

Exclusive ρ 0 electroproduction at HERA has been studied with the ZEUS detector using 120 pb -1 of integrated luminosity collected during 1996–2000. The analysis was carried out in the kinematic range of photon virtuality 2 < Q 2 < 160 GeV 2 , and γ * p centre-of-mass energy 32 < W < 180 GeV. The results include the Q 2 and W dependence of the γ * p → ρ 0 p cross section and the distribution of the squared-four-momentum transfer to the proton. The helicity analysis of the decay-matrix elements of the ρ 0 was used to study the ratio of the γ * p cross section for longitudinal and transverse photon as a function of Q 2 and W . Finally, an effective Pomeron trajectory was extracted. The results are compared to various theoretical predictions. PACS Codes: 13.60.Hb, 13.60.Le