2021 journal article
Global QCD Analysis of Pion Parton Distributions with Threshold Resummation
PHYSICAL REVIEW LETTERS, 127(23).
We perform the first global QCD analysis of pion valence, sea quark, and gluon distributions within a Bayesian Monte Carlo framework with threshold resummation on Drell-Yan cross sections at next-to-leading log accuracy. Exploring various treatments of resummation, we find that the large-x asymptotics of the valence quark distribution βΌ(1-x)^{Ξ²_{v}} can differ significantly, with Ξ²_{v} ranging from β1 to >2.5 at the input scale. Regardless of the specific implementation, however, the resummation induced redistribution of the momentum between valence quarks and gluons boosts the total momentum carried by gluons to β40%, increasing the gluon contribution to the pion mass to β40 MeV.