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arXiv · hep-ex/9704011

Differential Cross Sections of D*+- Photoproduction in ep Collisions at HERA

ZEUS Collaboration
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Abstract

Inclusive photoproduction of D*+- in ep collisions at HERA has been measured with the ZEUS detector for photon-proton centre of mass energies in the range 115 < W < 280 GeV and photon virtuality Q**2 < 4 GeV**2. The cross section sigma(ep --> D*X) integrated over the kinematic region pt(D*) > 3 GeV and -1.5 < eta(D*) < 1.0 is (10.6+-1.7(stat.)+1.6(syst.)-1.3(syst.)) nb. Differential cross sections as functions of pt(D*), eta(D*) and W are given. The data are compared with two next-to-leading order perturbative QCD predictions. For a calculation using a massive charm scheme the predicted cross sections are smaller than the measured ones. A recent calculation using a massless charm scheme is in agreement with the data.

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ZEUS Collaboration. 1997-04-23. Differential Cross Sections of D*+- Photoproduction in ep Collisions at HERA. https://doi.org/10.1016/s0370-2693(97)00422-x

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