A symmetry-preserving continuum approach to the two valence-body bound-state problem is used to calculate the valence, glue and sea distributions within the pion; unifying them with, inter alia, electromagnetic pion elastic and transition form factors. The analysis reveals the following momentum fractions at the scale ζ2:=2GeV: ⟨xvalence⟩=0.48(3), ⟨xglue⟩=0.41(2), ⟨xsea⟩=0.11(2); and despite hardening induced by the emergent phenomenon of dynamical chiral symmetry breaking, the valence-quark distribution function, qπ(x), exhibits the x≃1 behaviour predicted by quantum chromodynamics (QCD). After evolution to ζ=5.2GeV, the prediction for qπ(x) matches that obtained using lattice-regularised QCD. This confluence should both stimulate improved analyses of existing data and aid in planning efforts to obtain new data on the pion distribution functions.
Date of publication:
Chin.Phys. 44 (2020) no.3, 031002