2023/06/05 by Pei-Lin Yin, Yin, Pei-Lin, Yin-Zhen. XuID +7 · 5 citations
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Lattice (hep-lat) #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Nuclear Experiment (nucl-ex) #Nuclear Theory (nucl-th) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2306.03274
openalex publication_date 2023/06/05 · openalex created_date 2023/06/09 · openalex updated_date 2026/08/01
Parton distribution functions (DFs) are defining expressions of hadron structure. Exploiting the role of effective charges in quantum chromodynamics, an algebraic scheme is described which, given any hadron's valence parton DFs at the hadron scale, delivers predictions for all its DFs -- unpolarised and polarised -- at any higher scale. The scheme delivers results that are largely independent of both the value of the hadron scale and the pointwise form of the charge; and, inter alia, enables derivation of a model-independent identity that relates the strength of the proton's gluon helicity DF, ΔGpζ, to that of the analogous singlet polarised quark DF and valence quark momentum fraction. Using available data fits and theory predictions, the identity yields ΔGp(ζ\rm C=\surd 3\rm GeV)=1.48(10). It furthermore entails that the measurable quark helicity contribution to the proton spin is a0p^ζ\rm C=0.32(3), thereby reconciling contemporary experiment and theory.