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arXiv · 1912.07529

Drawing insights from pion parton distributions

Minghui Ding·Khépani Raya·Daniele Binosi·Lei Chang·Craig D. Roberts·Sebastian M. Schmidt
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Abstract

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 $ζ_2:=2\,$GeV: $\langle x_{\rm valence} \rangle = 0.48(3)$, $\langle x_{\rm glue} \rangle = 0.41(2)$, $\langle x_{\rm sea} \rangle = 0.11(2)$; and despite hardening induced by the emergent phenomenon of dynamical chiral symmetry breaking, the valence-quark distribution function, ${q}^π(x)$, exhibits the $x\simeq 1$ behaviour predicted by quantum chromodynamics (QCD). After evolution to $ζ=5.2\,$GeV, the prediction for ${q}^π(x)$ 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.

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Minghui Ding, Khépani Raya, Daniele Binosi, Lei Chang, Craig D. Roberts, Sebastian M. Schmidt. 2019-12-13. Drawing insights from pion parton distributions. https://doi.org/10.1088/1674-1137%2F44%2F3%2F031002

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