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The cross section for deeply virtual Compton scattering in the reaction ep → eγp has been measured with the ZEUS detector at HERA using integrated luminosities of 95.0 pb −1 of e + p and 16.7 pb −1 of e − p collisions. Differential cross sections are presented as a function of the exchanged-photon virtuality, Q 2 , and the centre-of-mass energy, W , of the γ * p system in the region 5 < Q 2 < 100 GeV 2 and 40 < W < 140 GeV. The measured cross sections rise steeply with increasing W . The measurements are compared to QCD-based calculations.

Coherent π+ and π • production in low energy neutrino reactions is discussed in the framework of the partially conserved axial vector current theory (PCAC). The role of lepton mass effects in suppressing the π + production is emphasized. Instead of using models of pion nucleus scattering, the available data on pion Carbon scattering are implemented for an analysis of the PCAC prediction. Our results agree well with the published upper limits for π + production but are much below the recent MiniBooNE result for π• production.PACS 13.15.+g 11.40.Ha 25.80.Dj