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Quark asymmetries in the proton from a model for parton densities

Johan Alwall·Gunnar Ingelman
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Abstract

Based on quantum fluctuations in momentum and of the proton into meson-baryon pairs, we develop a physical model for the non-perturbative x-shape of parton density functions in the proton. The model describes the proton structure function and gives a natural explanation of observed quark asymmetries, such as the difference between the anti-up and anti-down sea quark distributions and between the up and down valence distributions. An asymmetry in the momentum distribution of strange and anti-strange quarks in the nucleon is found to reduce the NuTeV anomaly to a level which does not give a significant indication of physics beyond the standard model.

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Johan Alwall, Gunnar Ingelman. 2005-05-30. Quark asymmetries in the proton from a model for parton densities. https://doi.org/10.1103/physrevd.71.094015

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