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arXiv · hep-ex/0702028

Leading neutron energy and pT distributions in deep inelastic scattering and photoproduction at HERA

ZEUS Collaboration·S. Chekanov
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Abstract

The production of energetic neutrons in $ep$ collisions has been studied with the ZEUS detector at HERA. The neutron energy and $p_T^2$ distributions were measured with a forward neutron calorimeter and tracker in a $40 \pb^{-1}$ sample of inclusive deep inelastic scattering (DIS) data and a $6 \pb^{-1}$ sample of photoproduction data. The neutron yield in photoproduction is suppressed relative to DIS for the lower neutron energies and the neutrons have a steeper $p_T^2$ distribution, consistent with the expectation from absorption models. The distributions are compared to HERA measurements of leading protons. The neutron energy and transverse-momentum distributions in DIS are compared to Monte Carlo simulations and to the predictions of particle exchange models. Models of pion exchange incorporating absorption and additional secondary meson exchanges give a good description of the data.

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ZEUS Collaboration, S. Chekanov. 2007-03-09. Leading neutron energy and pT distributions in deep inelastic scattering and photoproduction at HERA. https://doi.org/10.1016/j.nuclphysb.2007.03.045

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