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Quark Asymmetries and Intrinsic Charm in Nucleons

Johan Alwall
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Abstract

We have developed a physical model for the non-perturbative x-shape of parton density functions in the proton, based on Gaussian fluctuations in momenta, and quantum fluctuations of the proton into meson-baryon pairs. 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. We find an asymmetry in the momentum distribution of strange and anti-strange quarks in the nucleon, large enough to reduce the NuTeV anomaly to a level which does not give a significant indication of physics beyond the standard model. We also consider charmed fluctuations, and show that they can explain the excess at large x in the EMC F2c data.

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Johan Alwall. 2005-08-11. Quark Asymmetries and Intrinsic Charm in Nucleons. https://arxiv.org/abs/hep-ph/0508126

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