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Implications of HERA results for very high energy cosmic ray physics

Ralph Engel
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Abstract

Experimental results obtained with the HERA collider and recent progress in their theoretical interpretation are reviewed. After a short introduction to HERA physics, deep inelastic scattering and photoproduction are discussed as (virtual) photon-proton scattering. It is shown that the measurement and theoretical understanding of both photoproduction as well as low-x deep inelastic scattering are essential for obtaining reliable high energy extrapolations within hadron-hadron interaction models. Limitations of the predictive power of hadron interaction models due to the interplay of perturbative QCD and unitarity effects are discussed.

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Ralph Engel. 1998-11-13. Implications of HERA results for very high energy cosmic ray physics. https://doi.org/10.1016/s0920-5632(99)00216-9

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