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arXiv · 1410.8250

Pion Valence-quark Parton Distribution Function

Lei Chang·Anthony W. Thomas
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Abstract

Within the Dyson-Schwinger equation formulation of QCD, a rainbow ladder truncation is used to calculate the pion valence-quark distribution function(PDF). The gap equation is renormalized at a typical hadronic scale, of order 0.5GeV, which is also set as the default initial scale for the pion PDF. We implement a corrected leading-order expression for the PDF which ensures that the valence-quarks carry all of the pion's light-front momentum at the initial scale. The scaling behavior of the pion PDF at a typical partonic scale of order 5.2GeV is found to be $(1-x)^ν$, with $ν\simeq 1.6$, as $x$ approaches one.

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Lei Chang, Anthony W. Thomas. 2014-10-30. Pion Valence-quark Parton Distribution Function. https://doi.org/10.1016/j.physletb.2015.08.036

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