Narrow Results

Flavor symmetric sea quarks could contribute to the ratio of in the proton, as well as flavor asymmetric sea quarks. We clarify the isoscalar mesonic contribution, especially σ meson cloud effects in the meson cloud model. We also provide the meson numbers in the proton with different meson cutoff values. Our calculations show that a physical proton picture favors smaller cutoff of the examined range 1.0<Λ_ω<1.5GeV.

We review theoretical calculations for flavour asymmetry and strange-antistrange asymmetry in the nucleon’s parton distribution functions using the meson cloud model. We also discuss perturbative mechanism for the generation of strange-antistrange asymmetry in the nucleon.

Parton models predict several symmetries for the parton distribution functions of the nucleon, including flavour symmetry, charge symmetry, and quark-antiquark symmetry. We report calculations using the meson cloud model for the breaking of these symmetries.