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The production of neutrons carrying at least 20% of the proton beam energy (x L > 0.2) in e + p collisions has been studied with the ZEUS detector at HERA for a wide range of Q 2 , the photon virtuality, from photoproduction to deep inelastic scattering. The neutron-tagged cross section, ep → e ′ Xn, is measured relative to the inclusive cross section, ep → e ′ X, thereby reducing the systematic uncertainties. For x L > 0.3, the rate of neutrons in photoproduction is about half of that measured in hadroproduction, which constitutes a clear breaking of factorisation. There is about a 20% rise in the neutron rate between photoproduction and deep inelastic scattering, which may be attributed to absorptive rescattering in the γp system. or 0.64 < x L < 0.82, the rate of neutrons is almost independent of the Bjorken scaling variable x and Q 2 . However, at lower and higher x L values, there is a clear but weak dependence on these variables, thus demonstrating the breaking of limiting fragmentation. The neutron-tagged structure function, F

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The exclusive electroproduction of ω mesons, ep → eωp, has been studied in the kinematic range 3 < Q 2 < 20 GeV 2 , 40 < W < 120 GeV and |t| < 0.6 GeV 2 with the ZEUS detector at HERA using an integrated luminosity of 37.7 pb −1 . The ω mesons were identified via the decay ω → π + π − π 0 . The exclusive cross section in the above kinematic region is σ ep→eωp = 0.108 ± 0.014(stat.) ± 0.026(syst.) nb. The reaction ep → eφp, φ → π + π − π 0 , has also been measured. The cross sections, as well as the ratios σ γ * p→ωp /σ γ * p→ρ 0 p and σ γ * p→ωp /σ γ * p→φp , are presented as a function of W and Q 2 . Thus, for the first time, the properties of ω electroproduction can be compared to those of ρ 0 , φ and J/ψ electroproduction at high W .The ZEUS Collaboration